oh no, no, you are quite incorrect. _wb_ thought about doing something fancier at some point...You mean a maniac tree? AIUI that's built based on what's in the image, so it depends on the current frame contents. It'll be different for each frame, but the trees are stored progressively across the board - first you load the first pixel of all frames, then you start filling them in according to the new adam encoding (my recollection - haven't found anything in the pdf about animated storage yet).
and then he did it: (one shared MANIAC tree).