The baseball analogies are funny - pitching and playing the field are completely different skill sets. Murphy if I remember played both the 1 and 2 in high school has played mostly the 1 since he has been here (~35 games). Early in his freshman year he displayed excellent passing skills, but his passing and long-range shooting skills have diminished. I think its a combination of confidence, the roles he is being asked to play (to your point), the lack of talent around him, and the lack development/coaching from the staff.
To be clear, I don't want Murphy to go but he has regressed in some areas of his game, and the best way for him to reach his potential may be to get away from Gregory.