IMHO, SNKP wants to prevent Chinese Democracy Syndrome. by simply not raising expectations regarding release dates, they can choose the right moment to hype the game. it's hard to build speed from zero, but A WHOLE LOT HARDER if they have to push the release date back even once. and given SNKP's current state, i think it takes only a couple of syntax errors to derail their schedule.
also, Bill Gate's once said: it's better to have a piece of &^$% at the right moment than the perfect program at the wrong one. with so many mainstream games looming, timing the release of xiii anywhere near them is financial suicide.
my 2 euro cts.