Website validation myths

The "in-thing" now is a valid website. No longer can you write HTML code that has a few closing tags missing (sometimes a few extra tags) and get away with it...especially with the latest browsers, like Mozilla Firefox, having built in HTML validators, anybody can check the validation of a site (not sure if IE or any other browser has this feature. Does anybody know about this?)

But, recently I find that a few assumptions (like superstitions) have cropped up around this area. When clients came to me these assumptions I was like...whoa when this all this happed!
Below are few that really stumped me

1. A table-less, Web2.0 site is a valid site
   I guess the beauty and easy of use of such sites lead to this reasoning....but sorry to disappoint this is not so. A table-less, Web2.0 site is just that the word says. There are a number of sites that are Web2.0 and not valid (ping me and I can give you a solid list!)
   
   Valid website just ensures "markup validity"....that is the grammar, vocabulary and syntax of your HTML (XHTML) code is correct. It has nothing to do with whether you use divs or tables to layout your page.
   
   
2. Valid site means it will work on all browsers and operation systems
   Ha....you wish...we all wish. If all web-browsers followed the same standards the world of web-designers would be a much better place to be in (and even I would think of venturing into that area of the web!)
   Even 2 versions of the same browser do not use the same standards (sure you all must have heard the difference between IE6 and IE7...I agree the change is for the better but, have you tried to get a site work on FF, IE7 and IE6!?)
   
   Validity doesn't ensure compatibility. Like said before it just ensure that the grammar used while writing code is correct.
   
   
3. Valid sites ensure accessibility.
   Some of the accessibility requirements I have come across are (feel free to add or subtract):
   accessibility in browsers which have javascript/css disabled, disabled accessibility (like ensuring the layout doesn't break when the font size is increased about 3 times the size you specify) etc.
   As you see none of these are related to proper language usage, which is what validation means. To put it in a single line "No, that is not true".
   
   
4. The best one of them all "Valid sites ensure better search engine ranking"!!
   Good TEXTUAL content and keywords ensure good website ranking, not the way you have coded the layout. Layout in no way affects site ranking (good or bad way). Check the validity of some of the top sites and you will be shocked. (Note: that I have emphasized textual content. All other content is useless to a search engine)
   

Hope this list prevents someone out there from banging his head when a client tells him that his valid site is not browser compatible and isn't ranked in Google!

Until the next tech urge....