I know I'm replying to my own message,  but I do have a concern about
this that I want to ask about.

When a stable request is filed for a package, it is filed for all
architectures which have the ~arch keyword for the package and are
marked stable or dev in profiles.desc.

If an arch wants to stay marked stable or dev but only stabilize a
subset of packages, I think it is reasonable to drop that arch's
keywords from packages they decide not to stabilize rather than move the
keywords to ~arch. That makes it obvious that we shouldn't file stable
requests on that package for that arch.

What does everyone else think?

William