We are not a fast growing thin content site, our site has been around since 1998 and was getting direct traffic long before Google came on the scene. Our pages are handwritten and have taken over a decade for 4 people to produce. Think along the lines of a how to site. I will not be giving out the site url for what should be obvious reasons.
I posted my data to try and help Tedster and others pin down this oddity. One sidenote I wanted to bringup is that we do own many sites all under the same whois and on the same servers and only one of these sites has been throttled, all others are humming along and growing like usual.