Probably is an NZ thing
I've never come across them, but it strikes me that they're essentially accusing you of being too stupid to get your taxes right. Which would shit me too.
However, I suppose you could then take it that when they say it's unusual for them not to get you more money, what they mean is "err.. so you're smart enough to get it right yourself? How strange." and it's therefore a compliment.
(xanthine, Mon 31 May 2010, 6:12, Reply)