I'm confused. What's ridiculous about exhorting people to write kick-ass cover letters?
http://www.37signals.com/svn/posts/833-years-of-irrelevance
By all means, write a good cover letter -- but be aware that apparently unlike 37signals, some hiring managers do actually skim resumes when making the first cut. I'd feel irresponsible not doing so.
"Write a good cover letter", however, is not particularly novel or link-bait worthy advice.