We should look at it for what it is - a development exercise for the U21s.
If the player is already playing PL senior football they have nothing to gain from this competition, except some silverware that they probably don't value anyway.
Play the kids who are not getting regular first team...
Don't think we'll see first team regulars drop down, RDZ needs them for his own matches. Those returning from injury however are more likely.
I also think it's a little unfair on those who got us this far to then be dropped for someone who has parachuted in from elsewhere without any academy...