User blog comment:Mobo85/Jim Hill on the Future of Phineas and Ferb/@comment-3347644-20110924230103/@comment-3347644-20110925000758

I'll be joining you, Alternate Phin. Ha ha!

Maybe that was the initial purpose of 'Take Two' - testing the interaction between live action performers and animation. Evidently, it's worked well enough to warrant a feature film.