raf, I'm trying to get my fellow developers to write XHTML valid code, as well.
My arguments are:
1. It's the most up-to-date HTML
2. It's backwards compatible, and forwards compatible!
3. It is MUCH cleaner code
4. Less problems with syntax errors, etc.
5. It's a STANDARD! Standards are GOOD! I think that's the main point... developers need to realize we're on the same team and we should be coding to the same standard, so we're all on the same page...
Some of them are like "Why should I learn that? The code I've been writing for five years still works" ...which isn't always true, and I've pointed that out every time I've had to help them fix it - but I can see their point as well at times, even though I HATE to write sloppy code.
Example of some of the stuff I have to deal with (not the worst, and not the best, but an example):
<font face = arial +2><b><input type = text name = example value = "hi there"></b></font>
No quotes around attributes, spaces which shouldn't be there (which by the way screws up the current implementation of Mozilla, at the least!), font tags everywhere, unclosed tags, etc. ...and don't even ask what that "+2" is supposed to be, although I think it was an attempt someone made at font sizing?
I've got a few links that suggest reasons why people should write compliant code, and I think I've started to convince a few of them, but I was wondering if you had any additional input on this subject.
Personally I think just the modular aspect (i.e. stylesheets, no ugly font tags, external (and cached!) scripts) is enough it itself, not to mention browser compatibility, etc.... the only challenge is convincing other people to start writing clean (and standards compliant) code. :|
I've helped all of them figure out solutions enough that they're starting to see my point (and when sloppy or non-compliant code is the problem I make sure I point it out!), but any further nudges in this direction would be helpful.