Arm out of the Window.
I think you are spot on. I have always believed that it "flashes the field" as well. That is, realigning the polarity of the permanent magnet field windings.
It's possible that this would not be the case if you had previously selected the battery off - due to overtemp perhaps? Discuss.
This polarity may have been disturbed (reversed) or removed due to major fault on electrical system, which precipitated the genny dropping off line.
If you have a real "meltdown at 3 mile island" then heaven help you!
It's times like that you wish you had the simplicity of a Tiger Moth!
UG