I think I wasn't clear -- I'm not saying that layout's unattainable, just that there's no typability advantage from the staggered keys, because the click will still go to whatever key is occupying that pixel.

What I believe you were intending is that if a click is exactly centered between the Q and W, and only a pixel above the edge of the A, we'd count it as an A, and there's not a simple way to do that.

You're absolutely right -- I'd forgotten the title area still shows above the keyboard (and also, now that I think of it, the symbol keyboard has an even bigger area). Since the keyboard is not really fullscreen, there should be no trouble arbitrarily sizing it.