ws: Further thought suggests, as you indicate, that the 2-phase motor is rare, for I don't believe I've ever encountered one. Unlike the split-phase, however, wouldn't the 2 windings be "conscious" of neutral

Forgive the anthropomorphisms

Three-phase, however, are very common. Their claim to fame is that the direction of rotation can be reversed by reversing any two phases

Suggesting the question, wouldn't reversing the connection to a 2-phase motor also reverse it

You state that splitting a 2-phase supply would give you half the voltage. Now I've forgotten near everything I used to know about all that stuff, I agree that it would. However, if each phase were 115v, wouldn't the voltage across the two lines be 208 v instead of 230 v

Thank you again for your input, no pun intended

dalehileman