That would certainly force you to focus on your technique! Interesting.
Do you know if he was born blind or lost his sight later? Let us know if he decides to stick with straight shaving or not.
So he was born with sight but lost it at age of 4.
I let him first discover the sbape of different blades and scales, try different grips on a straight with a neutralised threaded (duct tape on it), marketing a Proraso lather in a bowl .
Finally, hé made a first shave under my supervision (note that word!) with a quarter hollow SR. Not cuts, some nicks ...
The main difficulties are the angle, the correct grip and the fact he forgets to wipe the blade when he reverses the movement.
But hé made it!.