Same kind of logic could be applied to Michael, he was a even more exceptional human than Oscar, not only did Michael, as a human, defeat Oscar, but he also killed his monster without dying in the process.
I also think it's funny how broken Michael could have been if he had been turned as a kid like Cole and the rest, I mean just think how easily he could have surpassed everyone if Michael had a over a decade of Superhuman life.
I mean think about it, as exceptional as the Mc is, or as brilliant as Deryl is, or as gifted as the moon twins are, none have that same cristal clear, ultimate single minded focus Michael has.
The Mc is strong as hell for a level 3, but how much time did he spend before and after turning into a Superhuman just goofing around ? pursuing girls and carnal pleasure, messing around with his friends etc.
Sure the Mc spent a ridiculous amount of time trainning no doubt, but someone like Michael ? Who seems to just eat, breath and sleep with only one ultimate goal in mind ? And train like a madman for the single purpose of gaining strength ? He would be unstopable.
I can't help but think Berhnhardt must have been a lot like Michael before he ascended as a Superhuman, just a exceptional human with a ultimate soldier's mentality. Who carried that single minded obsession and purpose over as a Superhuman and thus reached the top.