I edited and printed out that summary too and added it to my setup notes and 100% agree that it works I spent a while testing roll centre changes on my local indoor carpet track and adjusting rear roll centre once all other settings were dialed. I used rear roll centre to fine tune on and off power grip. I was suffering with off power rear grip and the car would oversteer or snap round too easily and was very unstable in chicanes. By lowering the rear roll centre by adding 2mm of shims on the inner camber link it solved the problem! You could feel it took away a little of the on power rear grip but not so much that the car ever broke free and was actually quicker once I adapted to the new handling.

On another track the rear was a little loose on power with the lowered rear roll centre but the off power grip was good. Here I increased the rear toe from 3 to 3.5 degrees and the balance was perfect.

I now use Roll centre to fine tune the car's on and off power handling on track. If changes to roll centre don't give me the required affect I use springs, roll bars, camber and toe then come back to roll centre to fine tune.

This thread literally gave me the power to set my own car up based on my own driving style and stop relying on other people's setup sheets. For a new car or if the setup has wandered off and I feel lost, I always go back to the kit setup and adjust from there. Although with the Xray T4 basic setup I always find 2.5 springs far too soft so tend to start with 2.7 front and 2.6 rear. The basic asphalt or carpet settings bring you back to a good known starting point that has often been developed by team drivers over a long period of time.