Brilliant theory.

I'm one of those people who got very close shaves with a Mach 3, and switched to straights for other reasons. But you're absolutely right – the stubble that comes several hours after a M3 shave was very sharp indeed, and very different from what you get with a straight shave.

Your theory explains two other things that have been mysteries for me:

- Why I never get ingrown hairs after a straight shave, even a superclose one, though I regularly got them w/my Mach 3;

- How it can happen that a straight shave is less comfortable than a M3 shave immediately after (i.e. aftershave still burns like hell, though I realize my technique needs improvement), but later in the day become far more comfortable than a M3 shave would have been.