I've heard the reference to razor rotation many times. Is this just because a guy has a number of razors or is there really a reason to rotate the ones you have?
It's an excuse to acquire/use more razors.
At one time there was this theory that razors needed to "rest" to let their edge recover it's shape after the beating it took from the shave. This effect has been observed on knives, and is probably also true for razors, but stropping also restores the shape of the edge without the wait... This idea that there's some sort of "need" for resting the razor was pretty well debunked once we realized that barbers used the same razor many times a day on customers and never seemed to notice this supposed value of resting them.