For me the signing of Fammy was a pivotal point as you suggest. When he came in LJ said he wanted to play a quick passing, high pressing game, which was music to my ears and which he delivered for a period.
But as soon as you bring in a big man to lead your attack that goes out of the window. Then he never found a way of playing that fitted Fammy's strengths (clue: he isn't a target man).
I have no idea why he went down that road, though I wonder whether Fammy was one of those "trading club" signings - get a season or two out of him then sell at a profit and ignore whether he fits a playing philosophy.