Rick,
Thanks for your explanation and excellent diagram. But I still don't fully understand how the Festool C12 clutch system works. At page 13 of the 2007 Festool USA catalogue, near the upper right corner, it states that "Torque shut-off is activated electronically--with virtually no mechanical wear. So is the Festool C12 torque control mechanical, electronic, or more accurately described as a combination of both?
Dave R.