Meh...Yes and no. Problem with that is that you run into a situation where a guy gets knocked DOWN by a punch/kick, and the ref stops the fight, even though the guy was fine. Either that, or the guy knocks the other fighter down, and doesn't pursue. The fight ISN'T called, and the hurt fighter has time to recover because the other fighter isn't allowed to follow through. For anyone who saw it on the undercard, Petz v Morgan is an EXCELLENT example of this. Petz REPEATEDLY knocked Morgan on his ass, but didn't follow through with strikes, because he (presumably) thought the fight was over. It was never called. Instead, he wound up getting a 10-7 round, and pretty much the most lopsided decision in the history of the UFC.

You can only do so much to protect these fighters. I see nothing wrong with hitting a downed fighter. You keep fighting until the ref stops you. It's like in all other sports....play to the whistle. The ref's do the best they can to step in, but if they take even just one second to step in, that could EASILY be two or three punches landed on an out opponent. I guess sometimes you just have to leave it to the discretion of the fighter on whether or not to follow through on a knockdown. Sometimes they make the wrong choice and beat on a guy who is already out, sometimes they make the wrong choice and allow a merely stunned fighter to recover, and sometimes they make the right call and the fight is ended without further injury.