AE is very inefficient! A clunky piece of crap you might say.
try cloning a clip in the same location for 12 frames using -1 frame for the source, you will see how pathetic it is. Adobe has been focused on features for the last few years, ignoring performance! Very frustrating especially on the MAC. Lets hope the New Mac Pro changes this, primer seems to be making headway, now how about AE Adobe?
Thanks, Mark