I seem to be in the minority here, but with 45mm tires I don't think you have to go anywhere near 100psi, or even 80. I weigh 245-250 and run 35mm Paselas at 80-85, 50mm Schwalbe Big Bens (actually 45mm wide on my wheels) as low as 45psi. I ride dirt and gravel roads a lot, the roads here are marginal, and I haven't pinch flatted in 15 years.
There doesn't seem to be a measureable difference in speed in the real world--I've done the same 25-mile RT commute more than 2000 times in 30 years, on a bunch of different bikes with tires from 21mm at 120psi to the 50mms at 50, and my fastest time was on an old Bridgestone mountain bike with 1.9-inch Ritchey Quads, a combination tire from so long ago that nobody else even remembers it.