A friend of mine, Jennifear, has posted what I think is an excellent article on SnG strategy. (Unfortunately on another site but heh, she's a friend anyway )
I think she has done a good job of quantifying what CJ and EscapePlan have been talking about here - that tight early is not the optimal strategy for the experienced player.
Check it out - I hope it can generate some discussion here.
(BTW, this link is posted with her knowledge and permission).