Probably late to the party on this but I just found out and am really relieved all the trouble with my camera panning being choppy and laggy on a high end rig problems are solved.
refer to steam forums (has dev responses i believe) * 2nd post has what u need to change *
http://steamcommunity.com/app/230230/discussions/0/45350244969459495/if u need, google divinity original sin performance boost, first result
* new patch says they did work on texture streaming, but I didnt see any difference between 57-new patch, then found this fix and its night and day, smooth panning.
-- expect new patch with improvements similar without the risk of disabling all-together, --