Something to keep in mind is that most folks are running different motors (RPM's) and pinions. Mix that with the possible combinations of weights (skids,batteries, rockets, missles, guns heheh..) linkages/swash, servo arm positions, blades and personal preferences..you can see why the knobs are different on every setup.

I'm running a 3800 with 11T and my knobs are both at 12 o'clock position when i fly outside. But I can dial that around to 2 o'clock on the left knob and 12 o'clock on the right knob and it is much more stable for hovering around inside the house.. but with lower head speed.

All you really need to do is find out what works best for you and go with it. As long as your COG is dead on, you will know when you hit the sweet spot because it will handle and hover great and the tail will behave.