My take-aways are these
It's known they're giving up quite a bit. So if they're not getting anything from it, that is a problem.
and
The study would suggest that the gifted program is coming nowhere near these kids' capacities to enrich their learning.
and
It seems to hold back the gifties too... They are being forced to work at the snail's pace of the slowest which is hardly what his parents signed up for.
Possibly this is related to
identifying gifted kids -vs- identifying kids for the gifted program. This is not just a difference of semantics; There is a clear distinction.
Matching the program to the child -or- matching the child to the program.