Yeah, I mean there are flashes along the way before that for sure. I just think The Lodger is the first episode that I think absolutely couldn't have had any version interpreted by Tennant. The whole premise of the scenario requires Eleven. And yes, they shot The Eleventh Hour a bit later so that Matt and Karen both would have had time to settle into their characters. This is generally what you'd do in a film, you never want to shoot a character's introduction first. They were able to do that with the series because they shoot so much so far ahead of time. I think it helped. Flesh and Stone/Time of the Angels was first. Actually Matt and Karen's first scene was "Time can be rewritten"... which is interesting, because it's one of my favorite of the whole series. But it's also quite simple.