Not really because in the end, the goal is to score points. If you suddenly start converting more 3rd downs but still are scoring roughly the same amount of points, how important then is that increase in 3rd down percentage? I guess it has an effect on your defense who might get more rest but offensively, if you convert more third downs and scoring doesn't change, is it that big a deal?
Right now, while 3rd down percentage has increased, the scoring has barely moved. Now maybe the increase in 3rd down percentage will translate to more points down the road, but right now, I really think it's hard to argue that Cooper has somehow transformed this offense.