Maybe I'm just not really that familiar with these advanced stats. I'm looking at the link posted above right there. Gus's Corsi On is -7.80 and Gervais's is -4.19. Gus's Corsi Off is -7.38 and Gervais's is -2.65. Their relative numbers are -1.5 (Gervais) and -.4 (Gus). Now, I am not one to put too much stock into advanced stats, but Corsi seems to be THE stat that everyone here likes to talk about when talking about advanced stats.
I stress again that I am not an expert so maybe I don't understand it, but my understanding of this stat is that when Gervais is on the ice the Flyers are at a net -1.5 shots and when Gus is on the ice they are at a net -.4 shots. Then you also look at the quality of competition, which Gus plays better competition, but Gervais plays with worse teammates. To me, this leads me to believe that just looking at the stats, these players are pretty similar. The difference in Corsi is 1 shot. Gus plays better competition but with better teammates.
Again, if I a interpreting these stats wrong please correct me because I honestly know very little about them. But if that is a correct reading of these stats, they seem to prove my point. If not, then I would revert back to my previous argument that stats don't tell the whole story (which I stick to even if these stats do support my argument).