Seriously though, Jefferson scores best in isolation sets. The Spurs don't run many isolation sets. They run pick-and-rolls instead (since Parker and Ginobili are both very good in pick-and-rolls) so RJ only gets isos on broken plays or in early offense on semi fast break.
Jefferson also has shown some ability to post up but the spacing just isn't there to post up when Duncan is on the floor with him. The big just drifts down and clogs the lane, which makes the spacing difficult to enter the pass.
It's going to take some time to figure it all out. The Spurs need TP back to push the pace and that should help RJ. They also need the other players to realize when RJ has an advantage and not always automatically try to run a pick-and-roll like they do with every other perimeter player.