It was very thoughtful of Matt Cutts to suggest multiple ways a publisher can de-value the non-google ads they sell. I believe he also suggested redirecting through a robots.txt excluded page. That works too.
Recommendations from Google's official representative to the webmaster community of ways to stifle a competitive advertising medium are much appreciated, thanks Matt.
We also really appreciate the threats of being penalized or banned from Google if we don't follow your ways of de-valuing these ads. Pretty nifty how you managed to scare both the buyers and sellers of direct advertising links.
We'll all just switch to buying and selling Google adsense ads now.