I guess I want to clarify what I meant by talking about my son's Explore scores. If I look at his scores he got as a grade-skipped 4th grader, but compared them to the 3rd graders who took the test (my son by age should have been a 3rd grader when he took the test), then his scores look a lot better. Of course I can't say that he would have gotten the same scores if he had not skipped in the first place, but who knows.
And unfortunately without running live experiments on our kids or do-over time machines, we don't know. So I'd take the perspective that he got his best score possible in this scenario with the possibility that he might've had a higher percentile ranking if he had been retained but also likely a lower score (whether motivational or simply lack of access to more advanced material.)
I also don't want to fight and embrace ageism at the same time. (Though I am quite certain once DS does some Explore like test, I'll be cross-comparing against age vs. grade.)
