Since Romney uses other people as attack dogs (as do most politcians)this might/might not be a bad thing.
If your scenario developes (Trump endorses O) they wouldn’t need to cut his mike. All the audience would have to do is boo..or worse yet...laugh at him.
He’d melt as if Dorothy threw a bucket of water on him. As outspoken and non-p.c. as he is, he really doesn’t hold up well to criticism or ridicule.
For someone who loves publicity, it would actually be a brilliant maneuver. More free publicity than you can imagine.