I can say KP has complained a couple times the past couple years about how frequently he is used deep middle, and how rarely the ball comes his way.
But that isnt KP being upset about the scheme, rather being upset how often he was played in that role. Rolle was very poor as a deep safety, so fewell did not use him much there, instead depending really almost exclusively on KP there.
But with the show Stevie Brown put on this season playing deep middle, Fewell now has a guy who can split those snaps with KP, and let KP spend much more time up involved in the action.
Of course both KP and Brown are FAs, but them both coming back would be mutually beneficial to both.