Years ago, a friend who had watched it was convinced that she had done it live. He then showed me the sequence, and it did seem like ehe did at least some of it live. I don't remember it all well enough now. I guess that if the camera then moves to a dialogue scene with Clayton just heard in the background, that part probably was not live. Clayton had a very touching vulnerable quality.
Ah, so I guess you've already done searches on the FSM boards about those other movies.