As I stated previously, cooking a well done steak is an art.
It shouldn't take a rocket scientist to figure out that at higher temps, the marinate helps keep the steak moist while eliminating the dryness that normally occurs when cooking meat well done due to moisture loss. Also a proper marinate helps break down the meat fibers so that they are softer therefore your meat once cooked is tender. So your "quality of the meat" theory is faulty.
Most people have been duped or belittled by the food & restaurant industries to believe that well done steaks are taboo when the real fact of the matter is that many restaurants or cooks don't like to deal with well done steaks because they're harder to do properly because it takes more time & preparation than rare, medium rare or medium steaks cooked at lower temps.