Appreciate the stats but, from the post: "The value of traffic doesn’t vary by position ... In fact, the quality in position 1 tends to be slightly lower than position 2, and the quality improves slightly as the ads get lower on the page — these are small effects that can be ignored for practical purposes." Maybe my budget is too 'small' to ignore these small effects, or maybe I'm just cheap.
But of course Google would publish something that would encourage advertisers to bid on positions and drive click costs up ;)