Back when his books were my textbooks he still had email. I would have emailed him if I had known it was a limited time offer. Now I guess I missed my chance.
It's interesting to see how the problem of movement is handled in animation of wooden characters these days. The grandmother willow tree in Pocahontas has a somewhat segmented, plate-like feeling to her skin, but I was really noticing it in the 'Guardians of the Galaxy' trailer the way the plant creature's 'muscles' slid against each other like rigid vines, instead of stretching and compressing.
Would it have been cheating to make the loop teardrop-shaped like most coasters are nowadays? He'd spend more time running up or down and less upside-down. It would be more like Donald O'Connor in Make 'em Laugh. Or maybe that would be an even harder shape to run around. Not sure.