I don't see any indication that Calin was referring to UA's E+ when he mentionned Premium Economy, was he?

Could it be something like AF's Premium Voyageur? It is not only increased seat pitch, there is also one less seat per row and the seats recline in a shell. $300 extra/direction on YUL-CDG. Personally I would love to see AC propose something similar.

20% less load factor at 50% higher fare, is there a market for it?