Well inform him what you know, let him make his own decisions and let him use it effectively now. If he moves on who knows? Maybe he gets to keep it in college.
Yes I do believe his two seamer will be a go to, once he makes a comittment to the pitch.
It just enhances so much of the arsenal to have a moving fb. Particularly if you cut and sink it. Unless it's just super hot a flat fb can be a liability..the beauty of both (2&4 seam) is you have a "rising" fb into the mix and that tad more unpredictability...does that 3 finger "do" anything?