Ian said he didn't think he could win against Danielle. Dan didn't throw the final HOH. Ian mentioned that he guessed on a few of the questions--he got lucky.
I think that Dan is a psychopath--he lies so easily and does not show empathy for others. If Dan is a psychopath, it doesn't mean that Dan is a bad person (ie mass murderer), just that he can lie without batting an eyelash. He can, and probably does treat his wife very well. Pyschopaths can be very charming, but the key is they don't feel emotions the same way that most people do, which allows them to manipulate people (if they want to) the way that Dan ran the house this year.
I think that this edition of BB was one of the best ever--Dan made it to the final two when he was a dead man walking (best BB episode ever), and Ian won against Dan, even though the jury thought that Dan was one of the best BB players ever. What it came down to was Dan's methods--but the thing about that is he had to backstab people to get to the final two. If he wouldn't have done that, he would have been sent packing weeks ago.