I do think that Noel can play with Embiid, but it is clearly a work in progress. Noel has been spending more and more of his time in the high post or at the foul line and they have clearly told him to start working on that shot (he isnt bad, but it is a work in progress).
Noel will never be a strong "defend a guy posted up" defender. He just isnt big enough, and while he might put on some weight and strength guys like Monroe will always give him trouble. That isnt a big problem as they give Embiid no trouble at all. Where Noel can excel is as a PF guarding the quicker, smaller big guys who want to shoot intermediate shots. Noel in that position provides great help defense as a shot blocker.
The league has changed to fewer and fewer low post guys. Guys like Noel are very valuable for their ability to intimidate shots, but not when he is on a guys back or against a strong low post player (but there are fewer and fewer of those guys).
I think Noel has a place with Embiid, but it does depend a little on which team we are playing. The nice part about Noel is when the other team takes out their top post player it allows Embiid to rest and Noel can slide into the C position.
Some of this has to do with Brett Brown also. So far he has allowed the other team to dictate whether we go big or small at any given moment, we need to change that. Brown needs to start sticking the "big" lineup out there and force the other team to try and stop it, that involves the 2nd big learning to work with Embiid and better guard play.