I believe the answer to your question is no. All other variables the same, it ill be impossible to gain more by moving the RR out unless like Legend said, you run backwards. If you look at the physics of gravity, and centrifugal force generated during a left turn, the center line of the car acts like a lever. The RR in a left turn situation acts like the fulcrum to the LR. More like a catapult would. The closer you move the fulcrum toward the center line, the more weight is loaded, and the easier that weight is to load onto the RR. The further out, the exact opposite, so the transfer of the lever would be slowed.
The available force carried through the turn is the same, the further you move the fulcrum the less Newtons are transferred to the track. On a LM, you can manipulate the newtons transferred ultimately to the RR tire patch in a few different ways, and accomplish the same thing.
To really see this is action, watch how often karters will slide rear hubs