Brilliant, just the right amount of magic. The explain feature is what really sold me that you thought about users! I wonder if I can put a bit of humanfriendly support in there with a pr.
I initially started using it because I found I could not control multiple screens well with gnome and friends. Moving windows between screens and workplaces, moving workplaces between screens, arranging windows.
Then I got addicted to the speed of flipping between windows and not having to fiddle with layout. Now I only have one screen but it is always the first install on a new Linux.
Nice small and configurable window dressing and i3bar were very nice also.
I think tcl is exactly in this niche. I haven't had time or an excuse to learn it, but it seems to fit perfectly. Haven't yet found out why it seems to be dying away