I have two comments on these excellent observations.
The questions you ask would all be similar to those asked by others reading the internal AH report. Don't you agree? Well, my hypothesis is this. Those questions were answered in the original and unedited report, but were deleted either for brevity or due to the fact that the information was deemed classified at that time. I prefer the latter. Reports at EK sometimes ran to a hundred pages, and were required to be complete. They were vetted before internal publication.
My other observation is the fact that Metol (Elon) is very acidic. Therefore, the pH drops as Elon concentration goes up. Readjustment of the pH is essential, but it does change buffer capacity. So, in the high Elon developers either the pH was low and left that way for some reason, or it was adjusted and that may have changed the developer. Again though we may not have all of the information.
I caution you not to overanalyze. I am sure that Grant meant this as a guideline and not a reference.