[TCLCORE] TIP #510 - what are our options?

I've been following the discussion on this TIP, and I'm reluctantly
thinking that it's less than fully baked. It's not available on at least
one major platform, with no apparent plans to make it available.

I'm wondering if we have an alternative, and one thing that comes to mind
is that we might expect it to be bundled on the platforms that do support
it.  This idea raises two questions:


   - How hard would it be to have a tk/pkgs that works the same way that
   tcl/pkgs does, so that extensions that require Tk and do not have full
   incorporation in the Core would have a place to go?
   - Assuming that tk/pkgs is a feasible path for packaging, is RBC in a
   state that it could be packaged in that way? I've not used BLT for a very
   long time, and I remember back to when I did use it that it required fairly
   extensive core patches in order to be incorporated; the BLT/[incr
   Tcl]/iTk/iWidgets set was something for which I maintained a separate
   'wish.' I'm presuming that our tireless refactory workers have allayed this
   concern?

I hope that the Mac developers don't see this question as 'cracking the
whip' - I appreciate the work you guys do, despite my ignorance of all
things Apple. I'm just trying to figure out whether there is a sensible
alternative to "put it directly in Core".