indeed, iirc, the 1998 usenix presentation by mckusick et al, seems to be an earlier record of (than the book) these s/w development models.

fwiw, both the gnu project and freebsd champion this (cathedral style of) development model.

however, i don't think linux or bsd is *purely* either approach.

w.r.t `user-facing software` which seems to be central thesis of gp, both the alternates (bsd/linux) offer almost an identical choice.