Spivak doesn't use early high school maths, of course ;) mentioning the fact that there is such a thing as an "evolute" is a good point, though - could I convi

Spivak doesn't use early high school maths, of course ;) mentioning the fact that there is such a thing as an "evolute" is a good point, though - could I convinve you to file an issue on the tracker so I don't forget about that? (HN threads disappear all too quickly!)