[ARC]

HOLDBACKS ALWAYS GOOD = WRONG
HOLDBACKS ALWAYS BAD = WRONG

Those who say that no child was ever helped by being held back are WRONG.
Those who say that every child that was held back were helped are also WRONG.

Too many variables. If a kid is held back and 'repeats' under a good teacher AND is placed with good students (his main peers), then it will probably help him EVEN if the original intent to hold back was for sports.

If a kid is held back and 'repeats' under a poor teacher AND/OR is placed with problem students, then it will probably hurt him EVEN if the original intent to hold back was not for sports.

Repeating a year with 'good' teachers probably doesn't hurt.
Dropping into a class full of thugs probably does hurt.
This is the reality. Just too many variables to consider.
It is rare that an extra year of maturity alone ever hurts, either socially, academically or athletically.