They're giving props to W+K in a backhanded way: "They wasted over six months of our precious time pitching concepts like people laughing while playing the game, and amusing card combinations coming to life on screen." That "conventional thinking" likely would have worked well and made the ad successful in conventional terms. So I don't think they're dissing the agency (maybe that's not what you implied), but rather saying W+K does well at a different kind of advertising. Non-potato advertising, say.