Yes, that is normal. Research shows that keeping a charge in the "middle" of the battery's range prolongs its life. So, the computer tries to keep the state of charge greater than two bars but less than (whatever the max minus two is)
I don't think that happens at all......at least not for that reason.The system will discharge itself by spinning a dead engine.
It's been discussed on PriusChat several times and I'v had it happen a dozen or so times.I don't think that happens at all......at least not for that reason.
What makes you think that running the gas engine will somehow discharge the HV battery ??