heh... interesting idea. i'd enjoy seeing a stat map of this if anyone can generate? my guess is the most common overlap would be a 7-8 inch penis with a matching shoe size, but that's a guess.
Depending in the manufacturer, I wear a 7, a 7 1/2 or an 8 shoe. My penis is not as versatile and is just a bit over 7 inches. Wife and playmates like it though as it is thick to boot (to attempt a pun).
i have a 10in penis but i wear a size 12 shoe so if yo penis is average so is your fot but if u have a big foot like 12 your penis matches a half an inch for each size thats what i think