Anyone have damage from blow-only winterizing?

Most TT & 5er manufacturers do not recommend more than 50 psi water pressure into the unit...Got to be a reason for that, whether a faucet is open or not....I set my air pressure when I blow out lines at 40-50 psi and open one tap at a time.....again, never had an issue either way I've done it, whether pumping in RV antifreeze, or just doing the blow out...