I have seen complex macros a lot and talked with the people that made them. Most of them just were not conscious of the consequences of their behavior. E.g thi

I have seen complex macros a lot and talked with the people that made them. Most of them just were not conscious of the consequences of their behavior. E.g this behavior is typical of someone that programs for a living but does not debug her own code, because someone else in the company does. So she is isolated from the consequences of her actions. For making them understand it is as easy as making the debugger people to program and the programming people to debug for a while. Nothing like making people miserable suffering from bad source code they have themselves created for making them understand. Then you give them solutions for their misery and they learn pretty fast. Experienced C programmers tend to avoid the trap of using heavy macros because they have learned. But at the same time they look for alternatives that make them more productive with some king of real metaprogramming.