To one of my questions I received an answer that I believe is partly wrong (see the comments). I felt that discussing the issue with the author of the answer was the right way, but I open it up here. John claimed that "a laxative should increase … transit time", but I don't believe this and I found a counter-reference, asking him to support his statement.
It wouldn't be unique even for high quality scientific literature to include contradictions. So if he underpinned his statement with a reference I would find it interesting and helpful. But if he does not? Shall I downvote his answer? After how long if he does not reply?
Shall I edit his answer to my question and remove the parts that seem to be wrong? How to do this without offending him?
What to do in general when a statement does not seem to be true?