fall HS league (using 'combo ASA/FED pitching rules) - meaning pitching can pitch either rule set if they chose (I know , I know... don't even start in on that
)
pitcher takes a legal position on the pitcher's plate, hands apart and pauses (simulates sign) , hands come together, then the pitcher does this:
Her glove hand separates and begins to arc backwards (as she would with her pitching hand) and stops basically pointing towards 2nd base. the glove hand then, changes directions towards home plate at the same time her pitching hand begins to arc backwards towards 2nd base. The glove hand then continuous to make a full revolution at the same time the pitching hand follows this motion (also making a full revolution much like her normal pitching wind up)
so all and all, you have a glove hand/arm mimicking the normal wind-up followed by the pitching arm (if one was looking at a clock on the windmill, the glove arm would be '15 minutes' faster than the pitching arm'. (ala King and his Court)
I was U1 and threw my left arm out and called illegal, but frankly, I am not finding any rule limiting what the 'glove arm' can or cannot do during the wind-up. Like I said, I think I missed it.