He's been disappointing at times, both on and off the ice, but he's only entering his 3rd season in the NHL. By no means a bust at this point.
He shows flashes of what people here expect him to become; the second comimg of Bertuzzi, which is probably unfair. Bertuzzi took 4 seasons before he put up 50+ points, 20+ goals, and that was on a last place team where he became a 1st liner/PP unit player by default.
Todd Bertuzzi for a time was one of the best, most feared power forwards in the world, and he made the Canadian Olympic Team. I'd never put those expectations on Kassian.
All he has to do is learn how to be a full time NHL'er, use his size, take the body, be mean and learn the game, how to read plays better and let his natural talents do the rest.