I also find it hard to believe that you can go 3-6 months without having to adjust your drivetrain. How much do you ride?
Why is it that everyone I ride with has ghost shifting and all types of noises coming from their drive train almost all the time? Why is it that I had such problems? Even on my road bike with ultegra I would have some ghost shifting and other problems from time to time.
Could it be that you just tolerate the occasional mis shift or grinding and I wont?