I really appreciate your testing.
Perhaps you could use a data acquisition system? I know this sounds like crazy high-end stuff, but I've been truly blown away by how easy and cheap the stuff is.
I recently purchased a couple DATAQ instruments devices for some testing I'm doing on my electric snow cat. You can log all sorts of stuff simultaneously; for example, I measured current and voltage supplied to a pair of DC motors. I'm not the most patient person for getting software running, but their free software worked great with little futzing around.
For example, the DI-149 allows up to 8 analog input channels +/-150V. The instrument plugs into a USB port and runs with windoze software. I think between your videos and some synchronized direct data gathering, you'd have an unbeatable combo.
- E*clipse