I'm an AdSense publisher and I get emails from Google suggesting that I add more ad blocks to my site, and also tips on where to place them to get noticed most - above the fold, primarily. They also coach on making the ads stand out by using bold/bright colours. I suspect you'd have to go above and beyond with your ad placements to frustrate Google...

I can see this becoming the subject of antitrust action.

Penalizing other people for advertising rather than relevance when they themselves make their money through advertising is going to be a problem.