He had 27 points, and was a 0.5PpG over the 2nd half, in his rookie season. Obviously he didn't have much opportunity to show anything this past year on the 4th line.
There is undeniable, untapped offensive upside in Kruger's game. I'm not saying he'll be a premiere 2nd line centre, but to say he's shown nothing in the NHL (which is in itself ridiculous) and thus won't show anything as he matures and gains more experience is naïve. He was in a role last year where he had to focus on defense and did a marvelous job. Next year, in a 3rd line role, he'll still have defensive responsibility but will have more freedom to make plays and create more offense. Whether he will/can or not remains to be seen, but the potential is there. It always has been.