Thinking back to my experiences in the program, there was a huge, readily apparent difference in the IQ of kids in the program versus "gen pop". In a regular class, the teacher would need to spend hours drilling the same concept, and still most kids would hardly grasp it. This wasn't a difference in maturity that could be explained by an 11 month age gap, but a literal IQ diff that persisted for the many years where I saw these peers.