kv5137,
The Underclass has grown a lot and it is heavily covered by colleges. However, I have to disagree with part of what you stated. It is true that the Jupiter Tournament is pro oriented, but more colleges (at least DI colleges) attend that event than any other event in baseball. Pretty much every top level college attends every year, usually with two coaches.
One reason is because no player is absolutely in the fold until the early "signing" period which is a couple weeks after the Jupiter event. So college coaches are there for two very important reasons...
1. To see and evaluate the talent.
2. To protect and further evaluate their commitments.
I think it might look like more college coaches at the underclass because there isn't the huge number of MLB representation that is so visible in Jupiter.
BTW, I have seen your son play "many" times. He is very talented and an outstanding prospect. Best of luck!