I would not advise to stick to number of stones so much. It is very individual. It depends on age, way of living, medications taken before, foods consumed.
The most important is the way you feel after flushes. If you feel great, keep flushing. Keep flushing untill all the symptoms Dr.Clark is talking about are gone. Then you will know. She could use the number just symbolically.
My friends had different problems and different flush results. But all of them similar in a way that they feel much better then before. Each of them has done at least three flushes. One got rid of allergies and sleeps much better now. Another one digests better. The third one feels she is full of life. It is a long list.
I, personaly, fixed my thyroid gland literally after my first flush. I look better. I am much stronger physically. And I managed to spend one whole year without taking a single pill or any other medication.