The other issue is rotational inertia, and is probably the main reason that racers moved to narrower (and lighter) tires. In a race, being able to hop onto a breakaway, and being a tick faster in a sprint, makes the difference between winning and losing. For recreational cyclists, being able to accelerate a tick faster is probably of much less concern than riding on comfortable tires.

I'm not entirely convinced by your model for pinch flats. Typically, these do not occur by having a whole section of tire pressed flat against the rim, but by hitting something sharp like the edge of a pothole. So the question is, if you took a 1/4" thick steel bar and put it across the tire (not along it or pointed into it) and then pushed it against the tire, how much force would be required to press it to the rim on a 700x23 pumped up to have the same rolling resistance as a 700x32 (e.g. 140 psi versus 95 psi)?

The one other comment that I'd add about the wide-tire, narrow-tire discussion is that the reason that a wide tire is faster at a given pressure is that the sidewall deflection required to make the contact patch is less. Narrow tires have to have more sidewall deflection because their contact patch is elongated. So to make a narrow tire have the same rolling resistance, you have to pump it up enough that the sidewall deflection is reduced. Of course, the smaller contact patch means that cornering ability is compromised.

Nick