"Ford maintains that Ford received no technical assistance from Toyota in developing the hybrid powertrain, but that some hybrid engine technologies developed by Ford independently were found to be similar to technologies previously patented by Toyota, so licenses were obtained." - I guess that means it's similar but not the same?...
My understanding is that the Ford Hybrid uses the 12V to power the spark plugs to turn over the engine and to run the electronics.
There is no way to jump the 12V battery using the hybrid battery unfortunately. There is a way to do the reverse though, as the car won't start either if the hybrid battery is low, it allows you to use the 12v battery to minimally charge the
HV battery.
I sat in the car yesterday after taking the key out and waited for it to feel the battery drain and switch to power off. It powered off the dash cam about 10 minutes after the key was taken out. So it's managed to drop the 12V battery from 12.6v (approx) to 12.4v in that time. Seems awfully fast.