I guy with a patch I used to play
About 25 years ago, I used to play a guy that wore a patch
in a "saloon" (yes, saloon, they even kept it as part of the name
from the old days) and that guy shot pretty darn well on a bar table.
I remember playing him many times, and it was always a good
battle. I actually experimented about a year ago with covering
one eye a few times just for maybe 5 minutes at a time, with a
patch to see if it would *help* me see straight down the line
of the shot. I found that it provides a much different experience
in aiming, as I was not distracted by the double image I would
normally see when looking down over the stick. I suspect that
your friend will do just fine, and I wish him the best.