Fundamental truth = no code should ever trust its input. Break this rule never. If you have optimization problems, then don't worry because they're better than

Fundamental truth = no code should ever trust its input. Break this rule never. If you have optimization problems, then don't worry because they're better than security problems and the hardware will likely solve it for you by the time you release. Trust relationships between bits of any codebase mean 'not loose coupled' = fundamental design flaw for simple, maintainable and secure code. Unix design philosophy: "do one thing and do it well" (and that means checking all your input religiously for every function)