Good point Benzmac. I checked the cam timing on my 250SL for reference. After finding it retarded 2 degrees, measured by a degree wheel on the cam, I reset the cam timing (advanced it) to enhance the engine's torque characteristics. The old sixes were relatively weak in that area.
Another point that I am wondering about, considering all the posts regarding timing chains and the crankshaft/cam pointers being X degrees out of line is: are they talking about degrees at the crankshaft? The cam is off half as much, so 6 degrees at the crankshaft is not unreasonable nor should it require correction unless one wishes to fine tune the motor.