I have that in another text too, which states that Griffon-engined spitfires handled very differently to the earlier marks, largely due to the opposite engine rotation.
Certainly the rotation direction was a major difference, but from a basic handling point of view I think the comments probably related to the extra torque that had to be controlled by the same size tail feathers as the lower powered Merlins (at least until the very latest marks that had bigger tail surfaces) and the extra weight up front which affected the C of G.
It was generally recognised that the Griffon Spitty's were not as nice to fly as the Merlin ones. Though I have seen it written that the lastest marks (I think the Mark 24 and 47) were the nicest Griffon versions as they had the bigger tails.