Age Limits and the Olympics

If the Chinese gymnasts were underage (and there seems little to suggest they were not), then that would be problematic because China would have knowingly broken the rules to give themselves an advantage. But should that advantage be given to all? If athletes under the age limit are, in fact, the best in the world, shouldn't they be allowed to compete? Is it fair to subject children to the pressures of Olympic competition? Is it morally problematic to subject them to the regimen necessary to compete at the ultimate level? Does it do a disservice to the games to eliminate some of the world's best competitors, especially now that professional athletes compete in other sports?