This is kinda interesting too. Apparently Dan Hendo is retracting his comment for this explanation:
"If I'm standing up not making him vulnerable for shots and not striking, he doesn't have to defend himself. The ref might not stop it. With me adding one more punch to it, he has to step in and stop the fight no matter what. So I didn't know he was completely out until the second punch landed. There wasn't time to really think about the pros and cons of whether I should hit him again or not. It's too close. I did what I was supposed to do in that fight and at the end as well to finish it. That's what every fighter is trained to do, is finish the fight. I felt like I showed good sportsmanship by stopping right then and there. I didn't try to continue after the ref stopped it like a lot of fighters have done. That's just what I tried to joke about afterward and that's what people have a problem with."
"It could have been anybody," he said. "It just happened to be Bisping. Maybe I enjoyed it more. I had the exact same finish against Wanderlei Silva. I knocked him out and landed one more punch on the ground. It happened almost the same type of way. ... And I like and respect Wanderlei a lot more than I like Bisping, and it didn't make a difference. It could have been anyone out there, and I was still going to do my job and finish the fight.
"I don't think anyone would have had a problem or said a word about it if I wouldn't have made that comment. Obviously I regret saying that, and it might have been in bad taste, but I was a little bit maybe emotional at the time, and it felt good to knock out Bisping like that."