@Dr Herbie:

That goes back to my old feature demand. Let me have taskbar visible when running Metro App (include allowing Metro app switching).

And in all seriousness, it is already possible, StartDock already demonstrated how it was able to host Start Menu inside a Window Form. The resize argument is pointless because we can always make sure the Window From is not resizable (except switch to Metro Strip mode, in this case, you can also move the strip around.).