I assume you refer to his desire to hold off on cumming when we do get together by desensitizing the hair trigger? LOL. I know guys that do it all the time, just to last a bit longer - which IS nice, btw - ... I've told the guys I go out with - especially if it has been a while for them - that wasting their cum in the sink is a shame, and that I'm happy to help out when we get together - a quick bj or handjob at the beginning of the evening is a treat for me, knowing it will lead to a few extended rides later on....
If you cum quick, you can either do it all over me before we go out, so you can get all horny over me out in public with your cum on my flesh, or do it quick...the first time. Guys that reach orgasm quickly tend to have a faster recovery time, so round two happens soon. If it does take along time to recover, I'm sure I think of something for you to do to me until it happens.
Masturbate. It's like doing an oil change. Get the engine going then vroom on me.
Everyone deserves pleasure so I would never tell a guy not to. I masturbate too so it's only fair. I'll still be able to make him cum so no harm no foul.