I'm going to re-order your paragraphs here. Maybe that will answer your questions.
h2ofun wrote:
The other question I keep asking myself, if 150's, meaning real short, seem to be with the data a good fit for me, I just ask why do most others not ride equal if not shorter than this? My only answer is most folks do not spend the time, or money, to see if short cranks would help them with a better fit produce more power. Just look at this thread, have many tried much shorter, and then collected repeatable data on them? Not that I have seen.
Most likely, many other riders will also look at their higher effort results and decide that it takes too much pedal force to produce anything above FTP. Looks like you have evidence in that direction as well:
h2ofun wrote:
I still am, for me, amazed that at 150mm cranks, I continue to produce more power on my 5 mile TT loop than on 175's. Mentally I want the 175's to be better, but so far, have not found any test data for me that shows they are better.
About the only thing I see is on my ramp to 300 watts. On the 175's I have the leverage to get there. But on the 150''s I tend to die around 270 watts and have to stand up the rest of the way to 300 watts. Going from 200 mm to 150 mm cranks, and then dropping your target cadence from (say) 90 to 70 RPM , means that you now require 70% greater force on the pedals to produce a given number of watts. Apparently, you have sufficient leg strength and knee joint operation margin to pull that off - but many riders do not, and even you might find that if you ramp up volume at threshold power levels, you're going to find it limiting or else it will start to show up on your run.
h2ofun wrote:
Oh well, I only started this thread to show others what I was doing.
Never tried to say it was "right". But as usual, it seems to turn into a mob attack that of course nothing I, or Frank Day does, can maybe have some food for thought for others. :)
The bolded statement conflicts with the first paragraph I quoted. When you question "since this works for me, why does nobody else do this", and present your answer where you presume that your conclusion is in fact valid and put up a straw man, you can expect to have it challenged. Just sayin'.
Less is more.