The Mirrorball Man wrote:
I thought it curious that Ten should, while his regeneration was pending, talk about it being like death and a new man swanning off; after all, when he first appeared, having regenerated from Nine, he told Rose that he was exactly the same man (as Nine, with a new face.
I think Ten was a little bit precious and narcissistic about the whole thing, which is not entirely out of character. I'd wager that if the tenth Doctor ever met the eleventh, they would have a Second/Third relationship.
OF course, 10 was also doing this in part because RTD wanted Tennant's departure to be A Big Deal to viewers and to tug on our heartstrings.
Re the Ten-Eleven dynamic, I liked a scene when Eleven appeared in The Sarah Jane Adventures. SJ asked him how his predecessor went - he didn't really reply, just fixed her with this look. Which could have been interepreted in several ways. But I got the impression that he didn't want to think about how Ten went, for various reasons.