Fred was definitely a general. Leuthen? Rossbach? Hohenfriedberg? He improved on his predecessor's military, and he was tactically skilled. There's a reason Dupuy calls him a Great Captain of History, and why Napoleon referred to his victory at Leuthen as a 'masterpiece of maneuver and decision'. Dude could lead an army; does that not make him a general?
I thought the thread was about great generals. (Alright, keep Frederick the Great on as no 100 if you must.)