An interesting discussion of the DOCTYPE declaration in WordPress themes. Seems to me that Alex is spot-on with this: you can’t claim a theme as XHTML 1.1 compliant because you can’t know what gets added to it by the end user. Sure, the *theme* might be strict as a school marm. But if the end user chooses to add all manner of sloppy JS widgets for MySpace and whatever else, the final result is not going to be strict at all.
I confess that, even with my own blogs, the “strict” doctype is probably over-selling a bit. Some times – even most of the time – the blogs are not going to be XHTML 1.1 compliant simply because I am constantly experimenting with plugins. Whether those are my own plugins which are currently in a state of disrepair or those I’ve downloaded from WordPress.com just to mess with, there is always the possibility of being out of standard.
And to be honest, while being XHTML compliant is a goal, its more of an ideal than a practicality under the circumstances. For professional paid gigs, that’s another story. But for this little site, well, I don’t call it my hobby horse for nothing!