I think he is getting it a little wrong, put one ad on your site and you will get higher pay out from Google from that one ad,because they will put the highest paying ads on that one advert,the more adverts you have the less the click value is, but you will lower your chances of getting clicks with less ads,so yes the click value is higher but less ads means less clicks I always compromise and have 2 to 3 ads on each page
Quality over Quantity. If you're finding a unit out-performing the other two you might as well go with it.
Few things that i know.... It depends on where you have your ads. It is for sure 1 place will perform better than the other so test on couple of places to make sure the best slot. Less ad on your site will have the better ones. This means if you have 3 ads floating then last one will have the worst CPC/targeted ads so prefer only 2 slots. Load the best performing slot at the top of the page when you load it. You can control it using CSS.