I think we simply arent used to the 1h stab. It sucks, but I dont think its that OP. I mean if you compared dedicated Greatswordusers(aka easy winmode players) with dedicated 1h players, a Gsworduser does 80% more stabs then 1h users. There are exeptions I know, but this is still the general outcome.
And to the OP? I don't think you know how physics really work and even if you did, what the fuck does any of this have to do with Crpg. Its a game...who cares.