When you're no longer seeing yourself, in some ways. You're as close to being as you can be.I suppose that's consistent with the moment that the mind actually turns off, and is no longer questioning what you're doing. When the questions stop, that's when the real acting takes over. And trying to get to the point where the questions stop, "Would I do this? How do I feel about that as a character?" When those stop, and it's just doing X, Y, and zed, because that's what you'd do as this character, because you're inside this character somehow - that's when it really kicks off.