@ThisSuckersElectrical the behavior you recorded in park would bother me. I have only had in my vehicle once with the ignition on and in park with 0 battery range and I think temps were mid to upper 30s F and it started the ICE for maybe 20 seconds then turned ICE off for minutes and that happened 2 to 3 cycles. I agree it is what it is, but I think if I were sitting in the vehicle parked and it was "hunting" like that in would see if using the accelerator pedal would keep it running, I doubt it would though.
The accelerator pedal on the hybrids has no control over the ICE throttle functions those are 100% controlled by the ECM and the programmed algorithms. It is not possible to rev the engine increasing the RPMs. It is possible to force start the ICE by popping the hood with it in run.
As for it bothering me, I don't let it. Not worth it. I have still have the 3 years/36,000 mile, extended 8Years/120,000 miles, plus the 10 years/150,000 hybrid component warranties. In July I will have had it for 2 years and it currently has 17,777 miles on it.