I honestly think you'll get more out of them together than anyone would have if they were playing apart. They clicked really well together, and I think it's because of the off-ice friendship. And Grabo's always-carry-the-puck style matches Kuemin's preference to let others take the lead outside o the D zone.
That said, Kulemin is a bit of a mystery to me. I just can't tell what went wrong with his offensive game. It was like he suddenly didn't trust himself to shoot the puck. The decline was sudden and steep. Some have mentioned the Lokomotiv plane crash really shook him up. But, no matter what, you still have a guy that knows how to battle in the corners, and never seems to get tired at the end of a shift/game/or season.
Neither of them are leaders, or scoring machines. But they aren't quitters or lazy either.
At one point, it was the Leafs plan to have these guys anchor the 2nd line. It should be fun to see if that plan ever could have worked.