Now, as I understand it, "boom and bust" is just a term for economic bubbles. It may have been naive for Brown to think that he'd ended bubbles, as they're pretty well baked into the economy and are based upon the actions of consumers, but as he said while I was watching: "not one piece of policy, not one suggestion or effort to come together to solve this crisis". It was like watching one child try and fix a vase that he doesn't understand is missing pieces while another one shrieks "HE DID IT!", unaware that in fact Dad left the vase on top of the washing machine when he turned it on.
Brown made a token effort to absolve himself, mentioning that it was a global crisis and not based on the British government's economic policies, but on international banking irresponsibility, but he really didn't make the point very well. Overall, I was actually quite impressed with him, though - he's trying harder and going further than any other politician I've watched to try and "fix" the global economy.
I'm still waiting for someone to suggest that they turn off the washing machine before they put the vase back on it.