Originally Posted by Gergely
I think the opposite is true (at least from tyre-wear viewpoint), because on very slipery track you can go with less camber and have a rear tyre worn slightly conical to iniside. On really high grip tracks with fast sweepers usually you should adjust a lot of static camber and the rear outer tyre still has smaller outer diameter (conical to outside). In this case adjusting more camber-gain (shorter link) is very useful.
If you have big problems getting the tires to wear correctly it is more often a problem with too soft rims or excessive slop in the suspension.
Although it is true in higher grip you will need more static camber.
If the short link works is something to test at your track, as it can change from track to track. In general, expect more steering, and at some tracks better tractin out of corners (especially hairpins).
But it can make the car unpredictable and unstable under braking.
It's an easy change though. I have two sets of arms and leave the inner screw in place when I switch to the outer position. That way the change is a two minute job.