That's a cool trick for sure, but honestly, a hot towel can sometimes make the skin too soft. A good barber should check your skin type first, because for some guys it can lead to more irritation. The prep is important, but the real skill is in the razor work itself.
Lol my barber tried that on me once and my face looked like a tomato for two days. Guess my skin is just too sensitive for the fancy treatment. Still felt pretty cool for a minute though.