Was on a flight last week where a blind chap was on the aisle seat of an overwing exit row (with a sighted companion). Was a little surprised about that given what I've read on here previously, and when the a crew member who helped him with his hand luggage seemed to realise, she appeared to go and tell the No1. Body language suggested that the No1 knew he ought to be moved, but with a fullish flight apparently decided to leave things as they were.
Interested to know whether it should have been allowed or not.