however, the question is whether helping your kids be good in sports is really the most important thing in life. What does this do to a kid when they later learn that you did this? It makes it seem that excelling in sports is the #1 goal, so what if the kid isn't good or doesn't like sports? It's like the whole experiment failed, and they're the reason.

There are other problems associated with bouncing a kid ahead. We did it with our oldest in order to get her into the Chinese immersion program that had just started. We were out of area for that school, so we were lucky there was (literally) one last opening for her ... if she repeated first grade. We struggled with the decision and did it. I think overall it was good because speaking Chinese is a big part of her identity, and she got to go to China 3x and will likely use it to some degree later in life. Also, by getting her in, all of her siblings automatically were allowed into the chinese immersion program, so it's been a blessing for all of our kids now. So it was worth it ... but my daughter definitely didn't like some aspects of it. She always felt too old/mature for her grade, and many of her friends that were her same age graduated, went on missions, went to college, etc. while she was left behind.