I am making the point that if you blindly optimise for certain outcomes (e.g. ad clicks) you may not actually be getting the desired behaviour you want (users clicking ads they are interested in with the possibility of completing a transaction)

If the CTR is too high or completion rate is too low, you are likely to be banned, no matter what the Adsense TOS say. See this thread for comparison: http://news.ycombinator.com/item?id=2049105