Because many, if not most, of the methods already return something useful. And as I said in an earlier response, I need to have some of these codes (yes there are more than just true/false) available for a certain specific subset of methods, and so started reusing them for other purposes, since they made sense for some other things, including where a failure state could have different causes that I may want to handle differently. Sure there are other ways of doing it, and suggestions are welcome.

But even if I ceased reusing these codes there are still a small subset of methods that would required some variation of the style question originally posed.