I was watching that live and heard the helmets knock together, the refs assumed it was Mahomes helmet, when in actuality the Texans players knocked heads above Mahomes. The NFL folks in NY should have immediately alerted the referee to pick up the flag, I thinnk they screwed the pooch on that one. But let me digress, I played football n the 70s and have watched evey second of every Bears' game since then. What QBs had to endure back then was absolutely criminal. As a former linebacker I have to admit it was fun to hit a quarterback as hard as you could just to see if you get snot to come out of his nose. But the rules of today are probably reasonable, but the application is not. Referees need to wait a half a second before calling roughing penalties, maybe even have a refs conference to ask for help, because those 15 yards penlties can really affect the game.