From my past experience, anytime you make changes to the adsense layout, it will reduce your earning dramatically. Is it true for any of you? Is it true that if you have large rec vs. button, you get less value per click? That translates less ad to display to the visitors. Is this a true statement? Thanks.
That doesn't make much sense. Mixing things up can help adsense, especially if you have alot of frequent visitors.
as mdvaldosta said above, there is no fact in what you are thinking. In fact it will help increase CTR if nothing at all.