Interesting! I hope it can work out well for him - would love to hear about his experience if he gives it a shot. I've gotten good feedback from low vision and blind users, but I've also done my best trying to support VoiceOver in the most optimal way. If he uses VoiceOver, be sure to enable "Direct Touch Typing" in VoiceOver>Typing>Typing Style. Also be sure to go through the tutorials as that should give him the best start.