Excellent questions and excellent answers about how the stone grader works with the grinding wheel for one who wonders how the different grades of grit are accomplished on the wheel.
http://forum.tormek.com/index.php?topic=41.0
While it does not discuss what most new owners fear of the stone wearing away quickly because of grader use, it is alluded to in that it states:
"When the stone grader fractures the aluminum oxide crystals, it does not pull them out of the binder that holds the stone together." Jeff Farris
Thought this might be considered for new operator pointers.