I read the replies to my posting. My response in short: Maybe I ”spoke” too fast.
My conclusions were based on a few premises as I explained in my original post, some of which have been ”corrected” by some of the replies, most notably, Lydilos and health_nutty’s. Lydilos mentioned that some people STOP getting any stones out after a while, which I did not know, and which obviously invalidates my argument, as that was one of the premises I explicitly refered to. Health_nutty’s clarification that s/he actually did pass these soft green stuff at the beginning only to give way ...
[retrieve this message]