This sounds like a decent way to run an educational program but a very poor way to run a business (at least a VC backed one). You probably won't get enough volume by doing a hard screen. You need to ensure that your program is good enough that even moderate or marginal candidates come out able to find a job. Otherwise, your business is quite small.
I think you would probably need to sell a "first look" privilege to prospective employers. The program at UT required volunteers from various administrative departments to spend time supporting it, and the primary reason they did so was to get a peek at who they wanted to hire, ahead of competition (from other departments). Of course, this would only work in times of labor shortage for good programmers, but that is most of the time.
