Please correct me if I have the wrong impression wof, but you seem to be approaching his from the point of view that after the RTO, and possibly exceeding the brake limits, that the brakes won't work at all subsequently. They will, they simply won't have the efficiency you expect. Setting aside the welding issue and a subsequent take off scenario, you should be able to exit the runway, and still be able to stop the aircraft from a slow taxi speed. The brakes don't simply stop operating at all.