What you guys are talking about lately on this subject is almost exactly how at least some of the posters are describing in the flaccid girth exercise thread.
That is, forcing expansion while holding the length expansion in check.
I wouldn’t have brought it up, except for the fact that I have found these to really pack a punch. Other posters have written that they get their asses kicked from them as well. Just 5 of them at 30 seconds each will send me spiraling. Others have reported partial dysfunction for a few days, (I think). The guys reporting this look like fairly seasoned PE-ers.
So I am saying that based on my very, very limited experience that you may be onto something with shortened pumping. I am also saying you may want to try doing a few of these manual exercises. On the surface they seem to be wimpy, but in practice they seem to be rather extreme.
I do them as follows:
20-50% erection.
FIRST, ( to me it is important which grip to take first), take a grip just below the head. I apply pressure only on the sides, but that is my effort to keep it low intensity.
Second, take a grip as low as you can on the shaft, I press a finger and thumb into the scrotum to pinch off the caverns like I am taking a pulse.
Then bring the two hands together slowly, compressing the penis like a spring as the erection subsides. For me it takes 20-50 seconds.
I think about slowly forcing the air out of an air mattress while I am doing it. Just enough to keep up an increase in pressure, not enough to force blood to the surface.
I am no longer doing them due to how much they affect me, but plan on adding them at some point.
I know I am a new guy, and probably just over enthusiastic, but these might be a way of doing some hands on testing of longitudinal pressure.