Hardy hits harder than Matt Serra and has better stand-up as well. But I'm not using Matt Serra has an excuse as to why Hardy could beat GSP. I know Serra was a fluke. Of course, anything can happen in MMA.
As far as GSP's stand-up being weak, like dude said, it's not weak, just not one of his strong points and isn't world class by any stretch of the imagination. The guy is just so damn athletic and intelligent that he can't be bad or weak in any area of MMA.
You're just a cook...