From my prospective, it is more important to remember that books on style and practices are meant as general guidelines, they are not laws of nature that always remain true. Writing programs is too complex an endeavor to conveniently fit into methods of right an wrong (tm) : after all; how do you know which of the (possibly conflicting) qualities are important to me, how do you know my (partially contradictory) goals, and how do you know my present constrains? You have no way of knowing. It would be nice to simply follow rules. Does this work, in each an every case? For rules must work in every case; otherwise, I cannot stay confident whether this rule will lead to harm or profit.