I cried, wept, screamed, railed against a cruel fate and then decided to wander the interwebs for an easy way to pull this off.
You see, I had to create a split-screen animation, and there was no apparent simple solution. Using of the crop and pan and zoom effects caused more problems than they solved.
In the end, I used rotoscope, which I should have thought of originally. Except I had no idea that it existed, and even if I did, how was I supposed to know what it did?