I think there are several reasons CPJ's offense is not more widely used in college football. Not many of them have to do with likes and dislikes of 18-year-olds. Here are a few.
1. 3-0 Football requires a mastery of the read, timing, spacing, and awareness. If any of a number of these four things breaks down during the play, it won't be successful. To achieve mastery of these four things, repetition is the key. Over and over and over and over again, until it becomes muscle memory. That takes practice time, and when practices are limited by regulation, a team can only accomplish so much. That's part of the reason CPJ stated that the passing game needed to be worked on individually, outside of practice. It takes 100% buy-in by the staff. You can run this type of offense and do something else efficiently.
2. The QB reads for the 3-O (or Veer) are much more complicated than for some of these other spread option-read offenses. That takes time for QB development and success. Every time you change QB's there's going to be a learning curve. We've seen that. JN was better his senior year, TW was way better his senior year, VL would have been better this year, etc.
3. To make successful game-time adjustments, the blocking schemes for the O-Line, the blocking schemes for the A-Backs and WR's have to be tweaked real-time. This requires an intimate knowledge of the offense, it's strengths and weaknesses, and how best to counter certain defensive strategies. This knowledge comes from years of exposure. Most coaches don't have that knowledge base.
These are a few reasons why coaches may shy away from this offense. Add to this that it's not necessarily a "sexy" sell, and it becomes clear why other coaches tend to shy away from it. There are many other reasons, but I put these here as a few examples.
edit: well, while I was typing out this book, some of these same thoughts came from others. Guess that adds credibility? Depends on who agreed with me.