I usually don't have any problem understanding them; all those years reading Harry Potter, and then getting so into DW, I've learned most of them (which has really been handy; so far, I've had no complaints about my usage in my fic). That was one I'd never come across, though. :) I'd say that you people have the strangest phrases...but, then, you'd probably say the same about us Americans, lol!
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