ROOTSYS and configure --prefix

The thread [url]Problems installing root with --prefix=$HOME/.local seems to suggest that if one first defines ROOTSYS and then configures ROOT using “–prefix” then one gets a screwed installation.
I didn’t try it myself, but if this is really the case, then one should add an explicit warning (in big letters) in
And if you mention ROOTSYS there, maybe you could also add my notes from [url]Installing ROOT from Source

Well using ${ROOTSYS} in --prefix= causes a problem, not having ROOTSYS defined per se.

Cheers, Fons.