all og the empirical evidence says that the shorter rest periods you use, the more volume you need to make up for it. I like 2-3 minutes but I train with high intensity. I don't think you need to sit there and time the shit though, most people know around the 2-3 minute mark they are good and ready for another intense set. Outside of insanely long rest periods, it appears erring on the side og longer is better if you train with intensity. You need to be recovered in order to push again. I cannot see how anyone could take a pendulum squat set to failure, then shadowbox for 30 seconds, and be ready to go hard again. Anyone that does, or says they do is using a flaccid penis level of intensity.