The glove hand is a "no teach" IMO........Emphasis on proper mechanics of the lower body and throwing motion will dictate what the "other side" does to counter balance the system.........
Some keep the glove "closer" to the target line.........While MANY others move it away and back in........There IS NO absolute for this action.........
IF you are not careful, you will coach the athletisism OUT of the "natural athelete".............
The glove hand should be a "no teach"..........Anything the glove hand is doing is a reaction to other parts of the system........
Get the system right, and the glove hand will naturally work to provide balance AND stretch to prepare for the contaction of the whipping sequence........