You are correct that stones from the gall bladder can then move to where they block other ducts. PANCREATITUS is both extremely painful (even more so than the worst gall bladder attack)and extremely serious.
Pancreatitus results when the enzymes from the pancreas are blocked from exiting and back up into the pancreas. These enzymes are designed to digest food in the small intestine. When backed up into the pancreas, they start "digesting" the pancreas itself.
Because the pain is so intense, most people will end up in an emergency room. Also because the pain is so awful, the idea of removing the gall bladder seems a much better idea at that point.
It takes days and days of fasting to let the pancreas "settle down", but at least with the pain gone, the patient can decide on the options.
The very serious point is - THE PANCREAS IS AN EXTREMELY IMPORTANT ORGAN AND REPEATED DAMAGE TO IT WILL RESULT IN DEATH.
A patient does have to weigh the risks in allowing more flushes to possibly block the pancreatic duct. People who have no additional pain during the course of flushes (during or BETWEEN flushes) have more time to cause imporvements in their system. But for people who have gotten pancreatitis (who thus tend to get stones stuck in the common duct or other sphincters), the options suddenly become much less optional.
Personally, I could not face that level of pain again (from pancreatitus). I have had my gall bladder removed. The surgeon found it to be so fibrous, it was like a lump of concrete attached to my liver. The fibers had not only thickened the gall bladder lining to an inch thick, but the fibers had grown from one side of the bladder, THROUGH the stones (dozens on large ones, plus hundreds of tiny ones) to the other side on the bladder.
None of the thickening had shown on the three sets of ultrasound pictures that had been taken while I did two flushes. I had only had three very painful gall bladder attacks in the preceeding four months. No one had any idea that the gall bladder had silently developed such a diseased state.
A patient must carefully monitor the severity of all painful episodes while doing flushes. Your body will indeed scream when the pancreas is threatened. Western medicine has its drawbacks, but remember that it also has saved many lives.