I skipped 4th, and my parents turned down a skip from 3rd to 6th on social grounds. Their choice provided insufficient acceleration, but it meant no academic disruption in terms of class rank. I later cut out the last year of high school and received university credits in high school for first year. By university, I was 3 years younger than my peers, but it felt like there was no gap in any area. (I suspect male accelerants might have a harder time with the social side here.)
DS6 hasn't skipped per se, but has telescoped 1/2 this year in a mixed-age classroom. A grade 3 placement next year will still be below his functional level in most subjects, so I'm looking to place him in a mixed-age classroom the following year that covers grades 4-6, in case he needs further acceleration, and provide some acceleration on the side in math/science in the interim.
For DS, I'm very conscious about ensuring that his output in the core subjects is >=90%ile for end of year benchmarks, as well as ensuring he is housed in a phys-ed class with similarly sized students. Because he's very large for age, I have less concerns in terms of impacts on athletics/leadership/social.
Several of my family members have skipped one or more grades, from small-for-age males with early spring birthdays to late fall females of average size, all maintaining their academic standing. The females seem able to adjust to later grade skips, with several (including myself) concentrating their acceleration in their teen years. The males have only skipped in K/1/2.
My view is that you really have to consider the individual learner at the point of each skip, as the child's academic/social/emotional needs will vary over time.
