A question posed on FOF last night had me searching. This is what I turned up:

Fulham with Greening

Played: 21
Won: 9
Drawn: 6
Lost: 6

Fulham without Greening

Played: 15
Won: 5
Drawn: 7
Lost: 3

Interesting, eh?

UPDATE: The difference is even more striking in the league.

With Greening

Played: 14
Won: 6
Drawn: 4
Lost: 4

Without Greening

Played: 10
Won: 2
Drawn: 2
Lost: 6