The problem isn't going to be promising a recruit money, the problem will be that people will make it known that they will pay the stars and other starters cash. Because pretty much every recruit thinks that's going to be one of them.
The local car dealer is going to make it known that he pays star players tens of thousands of dollars, and the recruit that thinks that he's going to be a star will think that he's going to get that money. And if he does become the star, he will get that money. You aren't going to need to pay people up front, you are only going to have to make it known how much you are going to pay them once they get here.
And if you don't think that there isn't some rich former offensive lineman from someplace like Alabama that isn't going to make sure that it's widely known that he pays the Alabama starting offensive linemen ten grand a year or something like that then you must not follow this very closely at all.
On top of that, schools where they are the only game in town will benefit as the local businesses will use their athletes to endorse their products. In Pittsburgh, those businesses will go to the Steelers and Penguins and Pirates like they do now as Pitt players will not reap the same ROI.
Unless the NCAA can find some way to strike a balance where these kids can make some money while not having it become the wild wild west, then this isn't good for Pitt or schools like it.