I agree that form is temporarily and class is permanent; but in the case of Werner; the statistics suggest otherwise. In Werner last season in the bundesliga; he missed a total of 21 big chances in the league alone, second behind lewandoski; but he was able to mask that stats because he receives chances and opportunities and score many other goals for Leizpig

In Chelsea, Werner gets only 1% of service unlike when he was in Leizpig; and also he is second on the chart for players with more big chances missed missing 16 big chances at just game week 31, so to answer you, Is Werner a good player? yes he is, Is he a good finisher? Ofcourse No, Can he improve his finishing? I really don't think so, Chelsea are better off with another striker.