"A perfect 800 on GRE math is just 87th percentile."

percentile of what? of general population or of those who took GRE?

i assume the latter is much more accurate, a perfect 800 on GRE math equals to 87th percentile only means that test is way too easy for most engineers

maybe a perfect 800 on GMAT math is 99th, i don't know, but if so, that only means the test is way too hard for most business-guys (assumption: GMAT percentile is based on GMAT takers)

anyway it's hard to imagine that tests for engineer is easier than tests for business-guys. i have my own bias of course.