The problem with the traction master type bars is they bind the hell out of the rear suspension. It will prevent axle wrap up on accel or deccel, but it will cause the rear end to get nutty when cornering over certain types of surfaces.

 

I have heard this before, but after driving my 66 289HP-equipped fastback over 200,000 street miles, and numerous autocross events with them, I have decided it's pure bull.