I've mentioned before that I come from a sibling group who all were radically accelerated and entered college early. I have no regrets about my own experience that might be attributed to radical acceleration. There were some awkward moments along the way, but I think for our family system, we had sufficient family and community supports. The challenges also were not made any harder by the grade skips; they may have been made less pronounced in some cases. This is not going to be the case for every student. Parents really do have to make these decisions on a case-by-case, year-to-year basis.
One of ours has skipped two grades so far, and is on track for early college entry in the near future. That one is highly social, mature, and self-aware, with grade-appropriate work and organizational skills, and was entirely accepted by grade-mates back before we started homeschooling that particular child. Another is putative 2e, struggles with production, and is introverted, which is why we have not chosen to make the same grade skip choices. Granted, we homeschool, so we have a lot of latitude for making and unmaking grade skips, and for fully individualizing instruction. In an institutional school, there would be additional layers in the decision-making process.
