If he can run in the 4.4's, he is first round. That said, I doubt that he runs that fast. He is more quick than fast. He has great power and toughness. There is no way he drops past the second, and I think he will level around the 40th pick.
I see two weaknesses in his game. The first, as I mentioned earlier, is his speed. He does not really have that feature back speed. This is not a huge problem (at least, I dont see it as one) because he is strong and quick. He wont bust many 50 yard runs, but he wont get stopped behind the line many times either. The second is his hands. He is not asked to catch much at Stanford, and the Texans love little screens. I want to know if he can do that.
If the Texans are picking in the 20's, I would have not problem taking him. It may look like a reach now, and the draft pundits will kill us for it, but Gerhart can be the short yardage/power back the Texans need. And it helps Slaton get some rest.