Of all the things to attack from Clark, the Liver Flush is coming from the exactly wrong direction.
There are simply too many of us who have done it and seen what comes out to know that it's performing as expected.
I cannot and won't claim that everything that comes out is a "gall stone", because that would be silly. On the other hand, I've seen "chaffe", bile balls (soft green things), beige "tic tacs", and various other things come out from liver flushes. In fact, I've had stones come out from live gall bladder attacks, well before I knew what a Liver Flush is, so I know what real gall stones look like, and I've passed plenty of those, too.
Until you can explain away how my flushes produced the same kinds of stones I found embedded in feces before I ever did a flush, you have no hope of convincing me otherwise on this issue; my direct, personal experience trumps your inexperienced, biased opinion every time.