function-reference/install-functions documents the "into" function: "Change install location for dobin, newbin, dosbin, newsbin, doman, newman, doinfo, newinfo, dolib, newlib" https://gitweb.gentoo.org/proj/devmanual.git/commit/?id=d0ac737563e55a1c8e11ab51a4f583268de44853 The correct list would be "dobin, newbin, dosbin, newsbin, dolib*, newlib*, domo" (but we could consider omitting domo because of bug 595924).
Thanks; not sure what source document I was using, but I clearly got it wrong. https://gitweb.gentoo.org/proj/devmanual.git/commit/?id=38a0a3642a40300af4a16199a5acd2bfee7f49c4