Rooney in 16-17 had 13 goals in 71 games.
Gibbons in 15-16 had 6 goals in 63 games. year prior in 26 games he had 3 goals.
So in the respective lead ups, Gibbons and Rooney scored at pretty similar rates. If you look at a 2 year window Rooney slightly outperformed Gibbons in terms of goal scoring. Gibbons, aside from an 11 goal in 28 games burst in 13-14 was never much of a goal scorer in the AHL.
Rooney has shown a decent touch for goal scoring in the AHL, much better then he was in college. Maybe that's due to usage, (though I assume he hasn't gotten prime ops at the AHL), or maybe he's a late bloomer.
As a 4th line guy I feel there could be something there.