AA did shoot whenever he had a chance, though some from a distance. But now he never tries, may be due to lack of confidence. I prefer Redmond than him now. At least, Redmond can shoot. AA was bought as a striker.
It seems to me that 3 CBs only work when we sit deep at the back (e.g. vs Chelsea cup game). However, it does not work when we are pressing. Do we need to concede first before changing formation to back 4?