>This turns navigation into muscle memory. Cmd-2 is not "Switch to Terminal"; Cmd-2 is just the physical reflex of "I want to code." I don't look. I just hit the key combination, and the active workspace changes.

What happens when some app (like, say, the browser) binds Cmd+<number>? If I hit Cmd+2 right now it'd switch me to the second tab in firefox. Seems like a pain to have to rebind everything.