I knew no one *in real life* who was fooled - but that's limited to immediate family, plus online fans I met in person after encountering them on a discussion forum crammed to the gills with Snape fams. :) There were certainly people I "knew" in online fandom who would have bet money they would never read the words "Snape was Dumbledore's" coming out of Harry's mouth, and I presume they had their less obsessed counterparts out there among the readership as well.

But I agree, the big, well-managed surprise of DH was Albus's backstory and the revelation, finally, of his Grand Design for the Greater Good. I do not find the books disturbing, but perhaps this is because I do not take interview soundbites too much to heart. (Though I am not familiar with the interview you mean... I thought the last word on Albus was that he was Machiavellian and a puppetmaster, which I would not deny, but do feel, for myself, is woefully inadequate to the task of capturing the man entirely - he did have a godd side too).