I shave fast in planet fitness showers with a 4”x4” travel mirror, and I haven’t knicked myself. I’ve even gotten bold lately and I kindof go cross grain under a fairly prominent jawline and it still has gone smoothly. It has made it so easy it’s basically fun now. It’s about sticking with the angle they have set the face of the tool to. There is a flat side that the blade comes out of, plant that flat side flush and it shaves probably as perfect as realistically possible. If you’re familiar with wood planers and their broad flat undersides, it works the same exact way. Their product videos explain it too.