And that's a good point - I mean each 'doctor' was sort of their own person, even though they do carry over memories and feelings and the like, they're still new people essentially. Like I think Tennant's love for Rose didn't completely carry over from Eccelston's and I don't think Smith has quite the same feeling for her. So yea that's a good point - it's more than just a new face and body, it's a whole new aspect of his personality. Time Crash even sorta solidified that, while yeah it was just a funny thing, still sort of put it into words, where he felt that when he became Davidson's Doctor, it was a change of pace he wanted to keep. And I think he's got at least a little partial control over what his next form will be like - with Smith he kept the youthfulness and energy, but I think he was a bit more 'damaged' than he was prior because of what happened to him during his 10th. And 11 seems pretty 'damaged' now too. So who knows when Smith passes it on to someone else, I wonder if he'll return to being a youthful, energetic figure or be more serious and 'adult' again. I like the more 'fun' Doctors, but especially after last night's episode, I did see a lot of hints that he's sort of regressing to the way he was when he was trying to be "older and self important"