I have been using the PMBOK Guide since 1996 and I used the original consolidated version to prepare for the PMP in the days where there were no real exam prep books. I became a PMP in 1998 and since that time, I had been contributing to the updates of the guide. However, in recent years, I did not contribute much for many reasons.
Now, the PMI volunteers are working on the sixth edition and I did submit numerous comments. However, my comments were limited to the text provided. I had written a few articles on the changes and you can refer to these earlier articles. There are three articles.
Today, I want to include other comments. These will be published in two parts. These parts were actually chapters in a book that I am working on but decided to delete them from the book and will include them here.

Other PMBOK Guide General Recommendations

“Othrt” is used here since there were other recommendations on how to improve (apply) the guide, which we left in the book since they were about applying the guide on real projects in the real world.

Reduce unnecessary white space

We will start with what some might consider a silly suggestion.
The fifth edition has a too much white (empty) space due to poor formatting, in our opinion. Sometimes as much as 20% of a page is left white where that is not necessary nor logical.
There are thousands of paper copies of the community and numerous practitioners, and PMI members print their PDF copies. Therefore, this is not a sustainable or environmentally responsible act. We guess that we can cut 10 to 20% of the pages in the guide, at least just following simple and sensible formatting rules.

Removing ITTOs

We suggest removing the detailed discussions about input – tool & techniques – outputs (ITTOs) from the guide and moving them to the practice standards such as the practice standard on risk, scheduling, estimating, and others. We realize that not all knowledge areas have practice standards, but these would be of value.
With this recommendation, the PMBOK® Guide will focus on the key concepts for managing projects; as we discussed in the other chapters in this part. Also, the guide will be more user-friendly by reducing a great deal of the repetitive topics and focus on the interfaces between all elements in a practical way.
We realize this recommendation might be a shock to those PMP or PMP aspirants who have been told to memorize the ITTOs for the exam; which we do not agree with, and we do not even cover most of the ITTO’s in our classes.
We think this change will take out more than half of the pages.

Performance management knowledge area

This new knowledge area is not our idea, but a topic raised by a professional colleague and a frequent speaker at PMI conferences, Mr. Crispin (“Kik”) Piney. Mr. Piney was generous enough to write a blog post about which we have published on our site[1].

What to include in a revised PMBOK® Guide?

Should the guide address all of the points that we raise in these chapters? For more information on these – you might have to wait for the book; although we had covered some of these topics in past articles, like splitting planning.
The PMBOK® Guide cannot cover all of these topics with the necessary details. It would not be logical, nor practical, nor necessary. This is why this PMI publication is a guide to ‘the project management body of knowledge’ and not THE body of knowledge.
However, the guide should dedicate more than one additional chapter to highlight these points, similar to what we are doing in this book. Many of the topics that we address here are already in the guide and would require more emphasis within the existing chapters. Others, yes, they would require additional chapters. One possible approach is to add these topics (as chapters) in the first part of the guide with the first three chapters. Alternatively, our recommendation is to add a section to the guide with the title “Applying the PMBOK® Guide” or “Visualizing the Application of the PMBOK® Guide.”
The additional chapters would be significant to stress what is and is not included in the PMBOK® Guide, especially for professionals new to project management (even experienced practitioners), to understand the boundaries and the purpose of the guide. Without such chapters (section), professionals are going to continue to misunderstand some aspects of this important project management resource.

External references

If PMI and the PMBOK® Guide update teams do not believe some of these additional topics belong in the guide, then offer reference on where they have covered adequately.
With these recommendations, the guide might even shrink in size despite the additional chapters and processes that we are suggesting in this book series.

Closing comments

There will be many suggestions here, and we do realize some are controversial or debatable, which is fine since the PMBOK® Guide updates team can evaluate and make the final judgment, assuming PMI will authorize a major restructuring for the guide. We also realize some points might be sensitive, yet, we do believe the PMBOK® Guide must change or risk losing value.
In this work, we have included many links to blog articles and pages on our websites, in addition to the other organizations. These links will help the readers get more information if they want to explore these topics further.
 
[1] http://blog.sukad.com/20121123/case-for-performance-management-knowledge-area/