The gist of the article is the reverse of that. If your site goes down in the rankings, one quick thing to check is your Google crawl stats. To do this, you need to set up a Google Webmaster Tools account and look through the crawl errors.

I had this happen last summer and it was devastating to my traffic. It was a hard problem to diagnose because all the third party HTTP viewers had no problems fetching pages on the site - but the Googlebot did. Since then, the webmaster tools has added a "Fetch as Googlebot" feature that would have saved me a lot of headaches. It's really fantastic.