Yes, it's a little more difficult pinning down problems with the human body than in a piece of code, and these kind of functional problems even seem to have stu

Yes, it's a little more difficult pinning down problems with the human body than in a piece of code, and these kind of functional problems even seem to have stumped most of the medical profession. However I see it as an engineering challenge. Essentially you are looking at a complex system and trying to solve a problem in a piece of machinery that you don't have any information about. Sometimes working around bugs in android or iOS can involve similar detective work. In terms of IBS, there is very little doubt that in my own situation that stress causes the IBS rather than the other way around. Diarrhea during the week, followed by constipation during weekends. Or diarrhea preceeding before a novel event. These are repeatable and predictable - it just requires taking a close look at your situation and seeing if you can see any correlations. Unfortunately it can be easy to get fooled into seeing correlations that don't exist.