First 18 months (5 years ago) I used two hands, then realised I was using too much pressure, and for absolute certain pressure is the main cause of problems for beginners. I use one hand 95 % of the time, as really I only want a bit of pressure when I buy a new razor, thus a bevel reset where for a minute or so you are cutting that new bevel. I've compared touching up or finishing on your finest stone (SG 20)as being done best in zero gravity. Maybe we should send a razor and hone to the space station for a demo...interesting.