So there are ebuilds which use einstall even though Makefile seems to have DESTDIR inside... let's investigate them!
There aren't many examples of 'einstall' in the tree at all now, unsurprisingly. In fact, the last one appears to be: >app-accessibility/eflite/eflite-0.4.1-r3.ebuild:35: einstall ... and it's just been last rited. Let's close this.