I hate to be a person who jumps on a bandwagon, but I share the same feeling.
I didn't analyze and research the college running backs, so I am basing my opinion on the fact that Smithiak used a 2nd round pick on Ben Tate. I know that Slaton was a 3rd rounder, but it almost felt like he was sort of leftovers at that pick. We needed an OL, and used the extra 3rd rounder on Slaton. I think the true value pick, for us, was at OL (Duane Brown) and the 3rd rounder (Slaton) was a bit of a project--Remember that he had a down season in college, among other things that made his NFL stock drop. I wouldn't call it a pure gamble, but very close to it.
With this year's 2nd rounder, we allowed the Vikes to move up and grab the white guy because the braintrust felt comfy with Tate. It felt like this year we really focused on the two biggest holes: CB and RB. I still do not fully "buy" that we were gunning for Ryan Mathews. I think he was in the mix, but was not a true option that Smithiak felt would be available for us.
It felt like we were making a more educated, less risky pick with Tate. In the footage I have seen, he turns up-field very quickly when finding the running lane. There's no hesitation, and you can see that he has the smarts to let the play develop and trusts that a gap will open at some point. He commits.