I think you're right that little protein is needed specifically for muscle building/repairing and nitrogen retention. On another hand, I think I read somewhere that the amount needed to stimulate protein synthesis is more than the small amounts recommended by those scientific papers you read. The thing is those studies only take nitrogen retention in consideration, but they don't protein synthesis. And I think that protein synthesis is also important in muscle growth... or maybe is another made up term by the bb media to promote higher protein intakes....who knows. Some people also claim they've made more progress by upping their protein, but maybe it had nothing to do with the protein itself..just the increase in calories. Overall, who knows what the truth is...the only thing I can say is guys on gear need a lot more than naturals.
I personally hate eating too much protein, so my intake isn't that high, but its still more than the 0.25-0.3 gr/lb recommendation.