Originally Posted by
johnknappcc
Wow, really, now I'm curious. My SPD (mountain shoes, although I use them on a road bike) are crazy stiff, I'm not sure I could imagine them any stiffer.
I said typically. MTB shoes typically allow some flexing of the sole (some allow a lot, some very little) to make them more walkable. Road shoes typically have virtually no flex maximizing the power transfer.