I guess it comes with the experience - after you do couple of projects you start noticing things and patterns between those. After some time they start to fit together ("click") and make much more sense than initially. But there are things I was always finding absolutely obvious - in my opinion these never required any proof. One of them is: Stick with The Single Version of Truth within your project docs (and not only them). What does it suppose to mean? The best illustration would be a negative example of breaking this rule. The real life example from near…