I am one of those who learned the hard way... i got a stone stuck somewhere in my colon after flush no. 4... developed a pain, felt worse and worse... it was getting bad when Andreas suggested i needed a colonic. I didn't then because i was too embarressed, but i started daily doses of castor oil. it took almost two weeks, but i finally passed the stone. it was huge and i almost fainted from getting it out. After that I bought a colema board and always follow a flush with it.
will everyone get stuck stones? probably not... but it does happen and you should be wary of it. i have seen posts from others who got very sick because the stones stayed in many months. i have no doubt that, had i failed to get that stone out, i would have been very ill.