Lets say for the sake of converstion that you retake and do better and end up with a 172 (realistically a 2 point increase would be better than normal). You are now sitting on a 172 instead of a 170....... For Stanford this puts you in about the same boat anyway. Your GPA is still strong, but its going to come down to your letters of recommendation and your personal statement, just like it would have at 170.
I think you are way better off writing a kick ass PS with the extra time you have and not driving yourself crazy, or better yet go VISIT and make your desire to attend known.
I just dont think the different between a 170 and a 172 would be that big, and you cant possibilty anticipate a jump any bigger than that (realistically, everybody starting at 170 is very smart and good at the LSAT so it is tough to believe that you are so much above the average that you will see a bigger jump).
It can be done (as you have seen on the board) but it just doesn't seem worth the effort to me.