It's a tough call... which has priority? Shore power, or genset??
If you know you're likely to lose shore power (storm etc), you might start the genset to be safe. In this case, you want the genset to have priority and run until you say otherwise.
If you're running on genset and waiting on power to return, you might want the shore-power return to shut down the genset - but you might want to wait a bit to be sure it's hanging around too....
Either/neither/both are right.
