I think what he's done is great. Remember, even though we're talking about a vintage bike, that's not what he bought. He bought it to race and when he no longer had needed for that purpose, he adapted it to suit his needs as a commuter.
To me a commuter is one of the most noble uses for a bike and one where function far outweighs form. A comfortable seat is more important than one that matches.
I commute with an 80's bike that is almost all original. But if somebody gave me a good set of brifters, a decent wheelset to go with them, and their only condition was that I also use their ugly but serviceable seat, I'd have no qualms about taking them up on it.