pnearn you hit the nail on the head again. This 'low and slow' phrase can really be a bit misleading. For me personally, I always equated that with going back along the target line (the yellow line as you've shown in another thread). And then there's the issue of perception as well. Even in cases when I feel I'm taking it back on the inside, my coach has confirmed that I am indeed taking it away on the outside (perhaps so slightly that it's hard to notice).

iverson has also pointed out some good points here. I think I've been focusing too much on the target line and neglecting the swing plane (45deg angle)