What I find most interesting is that bodybuilders do, in fact, require more protein. 12% more is pretty significant too. A larger sample would be fantastic, as would various training protocols (volume vs frequency for example) potential differences for BBers carrying significantly more muscle than others and a variety of other variables. 6 subjects make a weak study but it definitely points to greater protein needs for BBers. It's a shame follow up studies utilized beginners and then even general athletes.
I don't know what muscle mags you are referring to but I've posted an essay by Layne Norton and some studies in a different thread you must be referring to. I find it odd you would be so dismissive of Norton considering your ambition. And leucine was recommended as a part of a whole protein source ingested with carbs in a 2:1 ratio, don't take it out of context.