Two notes:

1.  It seems that my trick to disable --force and --recursive on
non-GNU systems doesn't work.  Does the specifications have to match
exactly?  A prefix match like the one I was hoping for would be nice,
or is there some other way to achieve the same effect?

2.  I'm not sure if the zstyle thing is correct, but it's definitely
what you want it to do.  Is there a better way to achieve the same
effect?

Thanks (and enjoy)!