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I have read the reasons for not being compliant. Personally, I think they are weak. Truly, how many people use Mosaic to browse the web, much less this site, any more? If your HTML was well written according to the specifications, strict is the only real way to go, then you will save yourself, and other, a whole lot of bandwidth. There is a ton of unnecessary HTML in this reply page alone.
Plus, you get the "works in every browser" almost for free. There are couple older browsers where a heavily styled page does not degrade cleanly but tough love to them; lynx works just fine and just about on any platform. You seem to love the fact that you render on tons of mobile devices -- CSS2 has a "handheld" media rule specifically for that purpose. Your mobile users would no longer have to go to special URLs (if they still have to any more).
Basically, your reasons for using quirky HTML are lame. However, I am not going to be one of those who say "change it because it absolutely MUST be compliant." Sure, I feel that way but it is your site. Do with it what you want. I just don't think it is right for a web site about technology to purposefully scoff at the effort to keep websites working as they were intended -- on any platform without having to use special code. What are you going to do when browsers deprecate quirks mode?