It means he is a more efficient one. He shoots to score when it makes sense, and does not when it does not.
Honestly, I am going back to fit - Aminu plays in the 1st unit, he is irrelevant to the discussion since we are thinking about Melo in the 2nd unit.
If the idea is to have another scorer on the 2nd team at forward - just play Layman there a bit more and give him the green light. He is athletic, works on defense, can shoot off the dribble and currently plays only 14 minutes per game.
If Melo is going to be in the 2nd unit - who is he taking minutes from? Zach? No - they need defense. Turner? No - they need a distributor, Curry / Saucy - no, both are better shooters than him that you need next to ET. If Moe is out - you will replace Caleb/Meyers minutes - they currently played 14 MPG combined - some of these you really can't use Melo for - especially when there are bigger guys or the team needs rebounding - so solve the problem with giving Layman an extra 7 MPG with the 2nd unit - and allow him to score as needed. "Problem" solved.