Maybe things were different in 2004, but those forms do not cross paths with admissions decisions whatsoever, for at least the last decade. The financial aid office won't communicate with admissions until offers have been decided. MIT is actually one of a few schools that is need blind for even international students, but almost every top school is need blind for domestic students these days. They want to have a financial aid package available to offer at the same time as admissions, which makes sense, so submitting your financial info prior to acceptance would be necessary for that.
Yeah, I'm not suggesting that they would have done anything nefarious with that information. I'm just saying I liked the transparency of the Cambridge system. You'd hold an admission letter in your hand before anyone had asked any questions about money, making it very transparent that money had nothing to do with that decision. The possibility that you could end up in a situation of having an offer but no money would still exists, but then at least you'd know that that's what happened. If you put all the info on one form you have to basically just trust them to handle the information appropriately.
Yeah I guess also the sticker price of Oxbridge being lower may make this the better choice. Even though the majority of students don't pay the list price at top US schools it is a really daunting number, and so for low income students not familiar with the process I can imagine getting an offer without any info about aid would be more stressful.
