Flush indeed purges liver (intrahepatic bile ducts) and the gallbladder.
But, what comes out may, or may not be the size we think it is. Our digestion may clump together smaller pieces into the larger pieces, creating some larger objects.
Bile together with smaller stones might react with oil and might create larger objects. There are many possibilities. But, the fact is, our experience with Liver Flush is real. Our cures (or lack of it) is real.