I just read this at the link you posted....
"Less can be more: While our policies allow you to place 3 ad units, 3 link units, and 2 search boxes on each page of your site, placing the maximum number of ads on your page may make it look cluttered. If users can't find what they're looking for on your site, they may turn elsewhere for information."
And got this from Adsense two days ago...
" At least 259 of the pages on #*$!#*$!x.blogspot.com are running less than three ad units. Adding any of our top performing units (336x280, 300x250, 728x90 or 160x600) to prominent sections of your pages will substantially increase your ad impressions and overall revenue.
Add more units!
Across the pages we analyzed, you could potentially add at least 514 units on #*$!#*$!x.blogspot.com."
So which is it Google?