Yes and no! I don't regret it academically or even socially. My son (11) skipped 2nd and could probably have skipped 3rd. My regret is that now he is in middle school and while his age mates (neighbors, baseball team, etc.) are out playing, he has more homework. I think we've made him grow up awfully fast. He is a late July birthday so would have been one of the youngest if we hadn't skipped him. When he was in 4th grade, one of his teachers commented "We're asking him to do advanced fourth grade work in essentially a second grade body". So, sometimes, I regret that he doesn't have more opportunity to "be a kid". HE doesn't seem bothered by it, though, so maybe he is "being a kid" in his own way. Hope that makes sense.
Due to the amount of redshirting we have here, there are kids in his 7th grade class who are more than two years older than he is. Sometimes that is hard.
Given the same situation, I would do the skip again. However, we moved to a different school district before 4th grade (he was in a private school for 3rd) and sometimes I think it would have been a good idea for him to have repeated 3rd grade in the new district. The private school turned out to be lousy and he could have used the quality instruction the new district provided, especially in writing.
It is a hard decision and I, too, recommend using the IAS as a tool to help quantify the decision and take some of the emotion out of it.
For what it's worth, I started kindergarten early (at 4 1/2) and wish my parents had skipped me a grade. They didn't because my older sister was held back a grade and it would have put me in a grade above her. My mom says she now regrets that she put my sister's needs over mine.
