I don't think this is a thing. It's a trope here but I don't buy it. Either you have the talent to rise to the occasion or you don't.
If a player like Cozens is simply too good to go back to juniors you really don't have a choice but to keep him here and let him suffer the grind.
If there's anything that ruins prospects it's these stupid rules that don't let them play in the AHL.