"An animated feature film is now defined as a motion picture of at least 70 minutes in running time, in which movement and characters’ performances are created using a frame-by-frame technique."
Pardon the ignorance, but does that mean motion-capture can't be considered? If you had to tweak it, that could be frame-level refinement. Certainly data exists for each frame, and the end product on the screen is a different image each frame. Plus I've seen feature shots where the animator has several frames go by unkeyed, but as a professional he knows where everything should be / is going to be on a given frame even if he didn't nail it down.