During my endorsement training from the factory pilot, he pulled out a wiring diagram of why we should leave the generator switch on. So I do, and I have had no issues. Recently, I have noticed that everyone keeps disconnecting the battery as well, so like a good sheep, I now do that too!!
I figure that if you can remember to disconnect the battery, you can remember to turn off all the switches..but hey, that's just me.
moosp, why dont you just think of the generator switch as your battery isolation switch, because that is what it does? No STC, no mod, no cost.