Edited

My experience has been that using more oil results in LESS stones. I've tried it twice using 3/4 cup of oil and both times had much fewer stones. Plus I felt sick as a dog. I have far more successful flushes when I just use a half cup.

My second flush also didn't give much stones, compared to the first one. But it doesn't matter. Sometimes material is clogging the ducts and it has to come out first before the stones can get out. Whatever I get out is good and I'm grateful for it.

The next one will be better!