This directly from Guest:
You must hook up the AFD (alternator field disconnect terminals) to both the alternator and the external regulator for it to operate properly. Since you have an internal regulator, you cannot use the AFD feature and you will harm the alternator by going to or through the Off position of the switch with the engine running.
Note that nothing is said about going through batery1, both, or battery2 with an INTERNALLY regulated alternator.
Perhaps those that have said, they've gone through the off position have the AFD terminals and external regulators?
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