March to Your Own Standard
“By invalidating my entire site with this one line of code, I ensure that I am made aware the instant it matters. The instant this stuff starts to break anything in the real world, I will know. If I only had a few small errors on a few random pages around my site, I could easily miss the day when “the big switchover” happens and wind up with broken pages I don’t know about. And since this code is in the form of a server-side include, I can freely remove it with a few clicks.”
Read more about standards, compliance, validation, and more…