It's common sense that Hendricks won that fight
He beat the dog shit out of GSP and only stupid fanboys disagree
Why else did GSP go into exile?
Hendricks should have won 48-47. But Penn did worse damage to him (GSP had to go straight to the hospital after the first Penn fight, he didn't after Hendricks). And Hughes and Serra completely, 100% finished GSP, which was way worse than what Hendricks was able to do. For that matter, GSP won the 5th round against Hendricks -- he must have magical recovery powers if he can have the shit beat out of him and still win the last round.
Hendricks should have won on points, but he didn't do enough damage to GSP to win the last round (GSP should have been barely hanging on for the bell if he was damaged), or to send GSP straight to the hospital. Lots of cuts and bruises are not serious damage, Serra and Penn did way worse to him.
If a hard fight was enough to make GSP retire, he'd have retired after the Penn fight (again, straight to the hospital after the fight), and then definitely after the Hughes fight, and then the Serra fight. Hendricks was only GSP's fourth toughest fight.
Basically, GSP should have lost the decision to both Hendricks and the first Penn fight, but for some reason Hendricks gets way more credit than Penn did for bad judge calls. And thinking that GSP retired because of his fourth hardest fight is just odd - think about it. He got hospitalized but didn't quit. He got finished twice and didn't quit. But he gets a gift judges decision and you think he quits because of that? He'd been talking about retiring for years, Hendricks was just the his last fight. Unless you also think that Bisping retired GSP (ie that whoever you fight last retired you).
Serra and Hughes did way more to GSP than Hendricks did, and Penn did a bit more to GSP than Hendricks did. I think people just forget (or don't know) that he was finished twice, and hospitalized once.