It depends on your definition of excellent he's clocking, up 7 goals and double figures in assists in each of his first two seasons. That's either primarily responsible, or creating 17 PL goals a season at - 19/20.
Granted he was gash second half of the season - but I put that down to shennagins.
I define excellent as somebody who turns it on almost every game, not 1 in 5.