I'm curious what other standardistas think about this essay by Jukka "Yucca" Korpela that I stumbled upon this weekend. I thought it was pretty interesting, particularly having recently read Martian Headsets and Understanding HTML, XML and XHTML.

This is a rant that promotes validation and puts it down. The point is that if you don't know what validation really is, it won't be of much use to you, and could even be waste of time. Validation is simply a way of getting reports about complying with some formal rules. What would you do with the results if you don't know those rules?

While the whole document is probably of interest, there were a lot of things I already knew and that seemed fairly basic. However, the things I didn't know seemed particularly choice, such as:

Although there is really not much to be gained from using XHTML at present, many people have started using it. Then it becomes relevant that validation means different things for XHTML. The reason is that the metalanguage, XML, is considerably less powerful than SGML. For example, the XML DTD for XHTML 1.0 declares the tabindex attribute as CDATA, which allows virtually anything. In the SGML DTDs of "old" HTML, the attribute is declared as NUMBER. This means that in validating against "old" HTML, tabindex="-1" is reported as an error (as it is), in XHTML validation it passes. On the other hand, XML imposes restrictions that forbid constructs that are formally correct in SGML-based HTML but not actually supported by browsers, such as the shorthand <em/text/ for <em>text</em>, and this means that XHTML validation is pragmatically more useful in some ways.

And Korpela's conclusion comes down hard on the use of "Valid HTML" icons put out by the W3C:

It's useful to write valid markup, in most cases. But it's hardly useful to make a noise about it.

Analogously, it's useful to use proper punctuation when you write in English. This makes texts somewhat easier to read and understand, and it adds to the literary quality a bit. There are slightly different styles of punctuation, and you should choose one and stick to it. But it's hardly useful to make a noise thereof. Would you like to include an icon like "Checked SGUFDFY 42.5!" onto your pages and expect users to decipher that SGUFDFY 42.5 means some particular convention on punctuation?

So what do y'all standardistas out there think?

"HTML validation" is a good tool, but just a tool. Jukka "Yucca" Korpela