Dude's a European style MT fighter who won against another MT fighter. The only thing you can conclude is that Petrosyan is the better fighter.
like I said, MT defense is a must. But Petrosyan is one of the best boxers in k-1 and he showed it against that Vitaly guy(who lacks boxing). I used this fight for an example of what MMA would look like once striking in MMA evolves. You simply cannot go out in MMA and expect to fight like buakaw. The more you know about MT the less you will use it in MMA.