Can we all agree on RTFM? Which is, oddly, usually the answer in this sort of discussion.
In fact I had an interesting time reading the POH for a C152 yesterday and comparing the power settings I was taught to the ones in the POH. (The Cessna isn't my usual aircraft.) I've made myself a chart of RPM vs altitude for 65% and 75% like the one which is placarded in the PA28 I usually fly.