Similar question to my last one:

Can a stator be reliably tested off the bike? Or at least without having to put the left hand engine casing back together and start the bike?

You can test for continuity between the three phases, and check each phase down to earth on the centre steel part.

Between the three yellow leads you should measure approx 1 ohm and from yellow leads to metal frame infinite resistance.

So the test in the manual works whether the stator is on the bike or off? (provided the reg/rect is disconnected)

Yes.