Guess I'm in the minority, but I would let him. In small bits, of course. In general, WDW is a pretty safe and controlled environment, so by letting him off for an hour or two he will be learning and growing, but there is still a safety net. As a parent (mom of 3, ages 4-16), I believe that children learn maturity by actually doing. Give him freedom in small doses now, so when he is 18 and on his own at college (or 16 with a driver's license) he has already learned what he needs to take care of himself. If he messes up at WDW (say he loses his wallet with all his money, or neglects to show up at the appointed time, or spends on souvenirs vs. having lunch, or gets lost and has to ask directions) at least here it won't be the end of the world, just a learning experience. You could also make it conditional--give him a chance to meet you at a specific place on time, or lose the opportunity to go off again later. JMHO