If I think of something, half-way into it, I can throw it in there and it won't be so far down the line that it would be insignificant. However, I also like to completely focus on something for a certain period of time, and then be able to move on to something else.
When I did Yoda, me and three other people worked our asses off, and I was sweating every single day, it was tough as hell. Now that it's CGI, 24 people work on Yoda, and I get all the credit -- I do nothing.