I have mentioned in past posts that I believe the effects of the flush for many people is likely due to the many components of the flush, such as the OO(rich in vitamin E), the Epsom Salts (magnesium effects mood, and several enzymes), and fresh squeezed fruit juices (they retain much of their enzymes and pure vitamin C components). Of course, the intense contractions produced by the oil can have a profound affect on any blockages, keeping in mind that many of the biliary ducts are measured in micro/millimeters, not centimeters, and that efficiency of the bile duct system could occur with a very small amount of mass removal.
I also believe, and have found in myself, that the regular 'exercise' produced by the liver contractions that result in the bile release of the liver/GB during a flush, can assist the body in producing/releasing bile more efficiently than before flushing.
Having researched information about lipase and fat metabolism in the body, I have grown to believe that the reason many people continue to produce stones after many, many flushes is due to either an on-going insufficiency in bile(something affected as much by dietary nutrients as by liver production and release) or by lipase deficiency. Bile emulsifies the fats, while lipase breaks it down making it absorbable by body cells. It seems to me that if bile isn't sufficient, lipase can not adequately break it down, even if there is enough lipase for the job, so the tendency toward 'stones' would increase as the un-emulsified fat moves thru the digestive tract. However, if the bile secretions are adequate, but pancreatic lipase production is low then a person is more likely to get the 'green blobs' rather than stones.
In my opinion, while either scenario could occur, neither one is superior to the other, they just give the person a hint as to what aspect of her/his digestive process needs the most attention. The focus can change as flushing and diet improvements continue. As more lipase is consumed or produced, more fat soluble vitamins such as A, D, E, and K can be absorbed and utilized by the body. And as the biliary system improves, the formation of liver/GB stones can be reduced which in turn will improve digestion, vitamin absorption, and cholesterol utilization(big deal in hormone production). No stones are produce when both systems are up and running efficiently creating an scenario where the large dose of oil produces an adequate release of emulsifying bile and the lipase breaks down that fat to be absorbed into the body cells as needed, sending the excess to thru the body via the intestinal tract and out with the fecal matter as fairly clear liquid oil.
All being said, flushing has many benefits, though perhaps not as simple as just producing stones. It seems to me that the 'process' of flushing is more important than any one part of the regimen.