This should be required reading for every PM. As an engineer the point about "doing the mental gymnastics" is the single biggest difference between a good PM a

This should be required reading for every PM. As an engineer the point about "doing the mental gymnastics" is the single biggest difference between a good PM and a bad PM. Well written/thought out specs guide my development process, shape my tests, and help me focus on the critical components. Poorly written specs are a just a PM refusing to do his job. I have campaigned to have PM's fired for this reason alone. If you can't take the time to think through the problem on paper, why should I bother trying to implement it. Also, if you are a PM and you are trying to persuade devs without hard data, you are going to have a bad time.