Blackcat, I think that you've nailed it-- if it's about genuine desire to do right by the child's long-term interests,
while respecting the child's innate developmental arc, then it's
unlikely to be hot-housing.
It may still not (quite) be healthy, if the parents are not being realistic about that developmental arc... but then again, that tends to drift into "it's not really about the child that I have in front of me" as well.
If it's about the parents' ego--
at all, then it probably IS hot-housing, or something like it.
I also find it strange that hot-housing in athletics is seen as completely okay, and yet those same rabid parents who scream at their kids, the coaches, etc. from the sidelines of a soccer or hockey game think that, in general, a chess/competition maths coach for a 10yo is "over the top" and quite possibly "abusive."
Uhhhhh-huh. You keep tellin' yourself that. 
