I can't really argue with them but Berget has some serious competition. Eikrem, Cala, Burgstaller, ALF, Guerra, Dikgacoi, Adeyemi and Macheda. I'd say Berget probably trumps them because of the money we paid and he made zero impact.
I don't think Chamakh was a total disaster, I'd say Camp has probably been the worst as he's been injured and hasn't contributed.