[llimllib]

Doctors rely on an enormous number of heuristics and shortcuts exactly like this.

My wife teaches doctors, and so much of what she does is giving them rules of thumb much like this one.

edit: I want to note that I'm pretty ambivalent on the actual advice of the article, just commenting that doctors in my experience have a truly astounding collection of rules of thumb

[mjevans]

An expert in a field tends to be an expert of the rules of thumb, the references to consult when the rule of thumb doesn't deliver the desired results, and the nuances and exceptions that are the art part of 'science and useful arts' for their field.