What is Negative Branch Reservation?

Did you experience this utmost frustration when having implemented a solution or countermeasure to a problem, a new issue arises brought up by this fix?

This is what Negative Branch Reservation (NBR) intents to prevent.

Negative Branch Reservation is  a robustness test usually associated with a Future Reality Tree (FRT). It checks what could go wrong in the intended change process in order to anticipate possible negative outcomes.

In a Future Reality Tree, identified Undesirable Effects (UDE) are combined with “injections”, which are solutions or countermeasures to neutralize the UDE, a cure to the pain if you will, hence the name “injection”.

Yet some injections may have negative side effects, opening a chain of causes-and-effects developing what is called a Negative Branch, leading to new UDEs.

How does this happen?

Injections combine themselves with existing reality to produce some effect, this effect is either undesirable by itself or the cause of a new UDE further up the tree as the new effect can combine with existing reality and so on.

Being aware of this risk, Logical Thinking practitioners mitigate it with a scrutinizing technique called Negative Branch Reservation.

How to spot possible Negative Branches?

The search for possible Negative Branches is part of the Future Reality Tree scrutinizing, once the FRT is built. External* scrutinizers are invited to consider each effect entity of the tree and check if another effect can arise then the expected one. This includes the Desired Effects (DE) at the top of the tree.

*not being involved in the construction of the FRT

If somewhere a Negative Branch is likely to grow, the next step is to check if the injection causing it can be replaced by another one, without the negative side effect.

Chances are that the initial injection must be kept as no better alternative is found. In this case, the Negative Branch has to be trimmed.

How to trim Negative Branches?

In order to neutralize the UDE brought up by the Negative Branch, go back to the Branch’s origin and surface the underlying assumptions, using the if…then…because following the arrow from the injection that caused the Negative Branch to grow.

Look for a possible injection to neutralize or minimize the UDE. If none can be found at that spot, move upwards the Negative Branch and repeat the process. At some point an injection will “cure” the UDE.

As the cure for the Negative Branch’s UDE is an injection, this too must be checked for possible new side effects with negative outcome.

The robustness of the Future Reality Tree, and every tree in the Logical Thinking Process, is guaranteed by thorough scrutinizing.

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What keeps TOC confidential? (and me angry)

It is one of the frustrations for Theory of Constraints (TOC) enthusiasts: why is their beloved business philosophy so barely known?

No other, neither Lean nor Six Sigma had such a visible high-flying banner like “The Goal”, the (probably) first business novel*, sold over 6 million copies so far. If readers have been so many and as it is reported so thrilled by the content, how come only very few people know anything about TOC?

*The Goal is a business novel written by Eliyahu Goldratt and Jeff Cox. https://en.wikipedia.org/wiki/The_Goal_(novel)

In this video interview, Nicolas Hennion shares his views, answering Philip Marris’ questions.

The first question about the name “Theory of Constraints” was also discussed with Bill Dettmer, another TOC expert with a pragmatic point of view.

I totally share Nicolas’ frustration about TOC Body of Knowledge being overprotected and monetized.

In my case, I stopped my learning journey in the mid-1990 when Internet was still young and not that populated with available free material as nowadays, Amazon did not exist and buying books from foreign countries (remember I am a Frenchman) was expensive and complicated. I resumed studying TOC and the Thinking Processes developed in between in around 2010, buying carefully chosen second-hand books, still shockingly expensive.

I estimate I’ve lost 10 years in my TOC learning journey, being disappointed about the difficulties and costs to get to the educational material. I turned to Lean instead, and did well.

When the TOC old guard wonders why TOC is still confidential, they should rewind Nicolas’ interview and try to understand the way the younger generations operate; networking, sharing, hacking open source style.

Food for thoughts…

Related: Theory of Constraints is something great, except for its name


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How can Theory of Constraints help startups – Purpose, Goal and how to achieve it

I believe most entrepreneurs started with a brilliant idea, a new product, a smart solution, new services… and the underlying desire to write a story on their own, not for a boss.

The startupers then start up as the brilliant new offer needs funding and some structure to bring it to the world.

But how many entrepreneurs started with a higher Vision, a Purpose beyond their product, smart solution or new service?

Once the initial project gets some uplift and before the scarce resources are wasted on inadequate investments, a short pause to think about Purpose and Goal is recommended.

Entrepreneurs, what is the Purpose of your undertaking? What is your Goal?

Make money now and in the future” are probably chanting those who got their basics about Theory of Constraints, first edition.

I don’t think that making money is the main driver for startupers, because if it was, a majority would go for more secure ways to achieve their goal and startuping wouldn’t be that popular.

There must be others drivers, each personal to the entrepreneur. Whatever the Purpose is, it is a Goal that requires some Necessary Conditions to be fulfilled in order to achieve it.

And precisely here Theory of Constraints can help, providing guidance and a structuring process with the Goal Tree!

I described extensively Goal Trees already on this blog, but in short the Goal Tree is a logical network of nested Necessary Conditions, describing what is absolutely necessary to achieve prior to achieve the Goal.

Taking some time to verbalize the Purpose or Goal of the undertaking and listing the first Necessary Conditions will give guidance about what is required and what to focus on. With this high level description of requirements, the entrepreneur can wisely allocated limited resources to what is contributing to achieving the Goal and avoid wasting them on nice-to-haves or totally off-topic things.

The Goal Tree stands out among other tools and methods with its merciless necessary-logic base: whatever does not answer the “in order to achieve… we must…” in a robust and logically sound manner is to be discarded.

Besides its robustness, building the first, most strategic layers of a Goal Tree requires only about a couple of hours, provided the Purpose / Goal is clear…

Once the Tree is built and scrutinized, amended and declared satisfactory, it serves as a guiding map and a benchmark.

Over time, the entrepreneur should check how many of the Necessary Conditions have been fulfilled (turned Green) and what is still to be achieved to get closer to their Goal.

>Related: Goal-Setting Theory and Goal Trees

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What are Categories of Legitimate Reservation?

Categories of Legitimate Reservation (CLR) are rules for scrutinizing the validity and logical soundness of Theory of ConstraintsThinking Processes logic trees and diagrams.

As with most of simple looking methods and tools, it is easy to get trapped or misuse the seemingly simple logical tools proposed by the Thinking Processes. In order to prevent decision making and actions based on flawed analysis, the CLR provide effective rules to check and validate the logical soundness of the various trees and diagrams.

Bill Dettmer call them “logical glue” that hold the trees together. In “The Logical Thinking Process”, Bill provides a full chapter (34 pages on the CLR).

There are eight Categories of Legitimate Reservation:

1. Clarity: is used to check the complete understanding of a word, idea or causal connection and avoid ambiguous wording. All the trees and diagrams are also good communication support, it is therefore important to insure the content is fully understood by anyone, even people not involved in the trees and diagrams construction.

2. Entity Existence verifies the reality or existence of the stated entity in the reality of the scope of analysis or problem solving. Sometimes people confuse building logical Thinking Processes trees and brainstorming, adding entities which are assumptions but not proven realities.

3. Causality Existence is the next thing to verify. Does the cause really lead to this effect? It is then important to read aloud the relationship, for example: “if A exist, then B exist” or “in order to have B, we must have A”.

4. Cause Sufficiency looks for one (set of) cause(s) to be sufficient by itself to create the effect. In complex systems, several independent causes could lead to the effect (logical OR) or some causes may combine to produce a given effect (logical AND).

If one legit cause remains hidden/unknown, the injections (solutions) may not always prevent the effect to occur. It is therefore important to list all causes.

5. Additional Cause is the check if no other cause, not mentioned so far, could have the same effect.

6. Cause-Effect Reversal checks the possible confusion between cause and effect.

7. Predicted Effect Existence is the search for an (additional expected and verifiable effect of a particular cause. Dettmer states that this reservation does not stand alone, but helps to validate or invalidate causality existence. If another predictable effect appears with this cause, the cause exists. If the additional effect does not show, the cause existence is very likely invalid.

8. Tautology, also called circular logic, is checking if the effect is not the sole and insufficient proof or rationale offered for the cause existence. It happens mostly when the cause is intangible: I strongly hopped for good weather ==> the weather was good because I strongly hopped for it.

“Long arrows”

Looking for “long arrows” is not formally part of the CLRs but I see it as such.

Long arrows are logical relationships linking causes to effects skipping multiple intermediate cause-and-effects, usually because the analysts know the intermediate links and do not feel necessary to describe them.

The risk of long arrows is to confuse people who weren’t involved in the tree building and/or are not sufficient familiar with the subject or situation.

Long arrows may also appear as flaws in the tree construction, thus making people reading them or attending a presentation doubt about the robustness and soundness of the whole.

The only acceptable long arrows, which are purposely used, are for Executive Summary Trees. And in this case, some caution is advised.

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Goal-Setting Theory and Goal Trees

Goal-Setting Theory states that goal-Setting, when done properly, is motivating. A Goal Tree complies to the requirements of a motivating goal-setting, here is why.

Goal-Setting Theory

According to Theory, Goal-Setting (and the underlying objectives) helps to focus onto the Goal and keep focused. Set Goals tend to increase effort in order to achieve them. Once Goals are set, they reinforce persistence as one does not want to admit failure. Goals make us creative or make us learn when necessary skills are not mastered.

Yet good Goal-Setting requires:

  • Specificity, which means clarity of purpose, precisely specified objectives, etc.
  • Challenge or Difficulty, which make achievement a victory and more satisfactory. Goals impossible to achieve are not motivating, though.
  • Acceptance and commitment. Goals forced onto someone may not motivate much.
  • Feedback and appraisal. This is necessary for “calibration” and benchmarking.

The following video made available by Alanis Business Academy tells you a bit more about Goal-Setting Theory.

Goal Tree and Goal-Setting Theory

A Goal Tree sets a Goal, that’s why this logical tree has been created for. It was because many efforts got lost by not knowing what the Goal was that Bill Dettmer derived the Thinking Processes (TP) Intermediate Objective Map (IO Map) into a more suitable tool he called the Goal Tree.

The Goal is set on top of the Tree where it is very visible and symbolically well placed so that everybody know on what to focus. The Goal statement should make sense and be understood by everyone. The Goal is the reason why the organization exists, so being member of the organization obviously requires accepting the Goal and committing to achieve it.

The array of underlying objectives, called Necessary Conditions (NCs), should be verbalized in a clear and specific way. This is verified when building the Tree and checking it with the Categories of Legitimate Reservations (CLR), which also ensure the overall logical robustness of the Tree.

Many of these Necessary Conditions are not fulfilled when the Tree is built (otherwise the Goal would be achieved..!) and fulfilling them is the challenged required by Goal-Setting Theory. A decent share of these NCs will be difficult enough to keep contributors motivated.

In the same way, some necessary skills may not be mastered, thus giving opportunity to learn or find by-passes.

The periodic reviews of the Tree status give opportunities for feedback and benchmarking, as well as appraisal or eyebrows frowning.


Going through the requirements of the Goal-Setting Theory, the Goal Tree is not only compliant, but allow the whole (often strategic) intent to be stated in a clear logical way. Reading a Goal Tree is reading the storybook.

If Goal-Setting Theory needed a tool, the Goal Tree is the one.

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The origins of Logical Thinking Process

The Logical Thinking Process is the name of a book from Bill Dettmer as well as the name of a complex problem solving process inspired by Goldratt’s Thinking Processes. Over time, while teaching the original Thinking Processes, Bill realized it can also  be used for strategy deployment, not only complex problem solving. In this video interview, Bill Dettmer tells Philip Marris about the origins of the whole.

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First Logical Thinking Process Alumni Reunion

Bill Dettmer, with Marris Consulting in Paris, is inviting the Logical Thinking Process alumni to the first “alumni reunion”. This event is solely for professionals who have attended one of Bill Dettmer’s Logical Thinking Process workshops.

On January 21st and 22nd, 2016, Marris Consulting will be hosting two intensive days of interactive meetings at their offices in the Montparnasse Tower, Paris, France.

click for more information

As a June 2015 “graduate”, I will be there!

Bill Dettmer awarding Chris Hohmann his Certificate of Mastery

Craft an actionable future and bring your organization to a higher level

Craft an actionable future and bring your organization to a higher level” is the title we’ve chosen for Bill Dettmer‘s Logical Thinking Process training course. And we believe this title tells it all.

LTP invitation card

Click on picture for more information

The program in PDF format can be >downloaded here<

During these 6 days (2×3)* from January 13th till 20th, each participant will go through 6 steps, from refining the Goal of his/her organization to the elaboration of the action plan to achieve it.

*As the training course is high density, Bill put a week-end in the middle in order to relax (and have opportunity to visit Paris!), but also to minimize the impact on participant’s organization during their absence.

Bill will personally review all Logical Trees and coach each participant. Everyone will return with a full set of actionable solutions. Therefore all participants are required to come with a complex problem to solve or a strategy to be crafted and deployed.

I will be there on the host side, having gone through the course and got my certificate of mastery in June 2015, and be glad to welcome you in our offices, on the 27th floor of the Montparnasse Tower, the tallest building in downtown Paris, in front of the Eiffel Tower.


 Registration form is >here<

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10 signs you need consider Logical Thinking Process

Here are 10 signs pointing to the need to consider using the Logical Thinking Process in order to help you solve your complex problems and structure your transformation plan.

Don’t know what The Logical Thinking Process is?
>The Logical Thinking Process in a nutshell

This article was originally written to promote the Logical Thinking Process training course with Bill Dettmer and Marris Consulting in Paris, an event I am involved in. I could not help but replicate it here!

The Logical Thinking Process is a great help if You:

  1. do not know how to properly state your Vision and Goal
  2. are unsure about what is required to achieve your Goal
  3. are afraid of costly and questionable “nice-to-haves” your staff is asking for
  4. have no benchmark for orienting and monitoring all efforts
  5. have no idea how far your organization is from the Goal
  6. are stuck with conflicting objectives or constraints
  7. do not know what to do to close the gaps and achieve your Goal
  8. are afraid about possible negative side effects and obstacles of your plan
  9. are uneasy about how to communicate the necessary changes
  10. would like to have a list of prerequisites for successful change

1. You do not know how to properly state your Vision and Goal

Surprisingly many employees, from shop floor to top managers, don’t know precisely what the Goal of the company is or have different views on it. How can they align their contribution if the Goal is not clear or understood in different ways?

The Logical Thinking Process starts with a clear and unambiguous Goal statement, an absolute must in order to meet success. A powerful multipurpose tool will help: the Goal Tree.

2. You are unsure about what is required to achieve your Goal

The Goal Tree describes all required Necessary Conditions to be fulfilled for achieving the Goal. These Necessary Conditions are listed from a sound and robust analysis using only “necessity-based logic”, in a scientific approach.

3. You are afraid of costly and questionable “nice-to-haves” your staff is asking for

With the Necessary Conditions listed, only those complying to the logical “necessity-based logic” will be kept. All others, not strictly necessarily will be discarded.

This is a very powerful means to filter out all the personal wishes and “nice-to-haves”.

4. You have no benchmark for orienting and monitoring all efforts

Once the Goal Tree is completed, it is a system-wide benchmark of what is required to achieve the Goal. The Goal Tree is then used to check the status of each Necessary Condition and the overall progress towards the Goal.

A Goal Tree is valid as long as the business environment does not drastically change, so the few hours investment in building the Tree is definitely worth it.

5. You have no idea how far your organization is from the Goal

Besides the Goal Tree, the Logical Thinking Process provides other tools among which the Current Reality Tree, describing the actual state of the organization in regards of gaps to the Goal.

The Current Reality Tree is built starting from difficulties and problems encountered by the organization and goes down to the very few root causes, discovered using the cause-effect logic.

Treating the few root causes will solve many problems at once as they are only multiple Undesirable Effects related to a same cause.

6. You are stuck with conflicting objectives or constraints

Among the obstacles on the road to the Goal, conflicting objectives or constraints are common. To tackle these conflicts, the Logical Thinking Process provides a tool called Conflict Resolution Diagram. Based like the other tools on logic, it helps to debunk myths and false beliefs as well as find win-win solutions to conflicts.

7. You do not know what to do to close the gaps and achieve your Goal

The Logical Thinking Process depicts the desirable future state with a Future Reality Tree in which the previously listed obstacles and problems have been removed or by-passed with appropriate solutions.

The “difference” between the Current Reality Tree and the Future Reality Tree are the gaps to fill in order to achieve the Goal.

8. You are afraid about possible negative side effects and obstacles of your plan

Simple elegant or sophisticated solutions may look good on paper but can mess up more than solve current problems. Fearing something could go wrong and lead to a worse condition can paralyze initiatives.

In order to prevent possible negative side effects, the Logical Thinking Process provides “stress test” and robustness assessments. Among them, any possibility for negative side effects to develop is scrutinized.

If one pops up, an appropriate preventative countermeasure is defined. At the end of the analysis, the robustness of the solution is guaranteed.

9. You are uneasy about how to communicate the necessary changes

The Logical Thinking Process and its tools provide robust and straightforward means to communicate what the necessary changes are, why and how to make the change happen.

As everything is based on sound logic, it is free from any emotional biases and verifiable by anybody, making the communication very robust and compelling.

10. You would like to have a list of prerequisites for successful change

Everybody wants a clear roadmap and concrete examples about what is to be done.

The Logical Thinking Process provides a logical Prerequisite Tree, listing all steps and Intermediate Objectives along the path to reaching the Goal.

The Logical Thinking Process is surely the most structured and robust way to lead the transformation of an organization, from its difficulties to its success.

If one of these 10 signs applies to your organization, you really should consider the Logical Thinking Process.

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Invitation for next Logical Thinking Process training, Jan 2016

After the successful June 2015 session in Paris, Bill Dettmer will come back in January 2016 for a new Logical Thinking Process training session in Paris.

Subscribers to this blog may know my interest in the Logical Thinking Process, the Logical Thinking tools and Theory of Constraints at large. I am therefore fortunate to organize the training with Bill and look forward for this second edition in Paris.

After presenting the upcoming event with a short cartoon, here is the master himself, inviting for the January session.

Description and registration : http://www.marris-consulting.com/fr/Formation-LTP-description-226.html

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