I've been a "long term lurker" but after reading so much sh** (esp. about protein) in the mythbuster 7 discussion thread - I decided to sign up!
Some little math.
Let's say you build 1 pound of muscle every week - that equals 52 pounds of muscle a year.
1 pound equals 450 g // 52 pound equal 23,5 kg or 23500 g.
A year has 356 days and if you divide the 23500 g of muscle build a year by 365 you get 64 g of muscle build every day.
Ok - now start thinking: do you really believe that you need a protein intake of 300 - 400 g to optimize muscle growth? Well - no! The optimum protein intake for an adult male is about 1 g of protein per kg - so a male adult with 200 pounds (91 kg) needs about 90 g of protein daily.
To the 90 g protein needed add the 64g of protein needed to build the muscles (and add 50% just to feel better) - and you get 90g + 90g = 180 g protein!
There is NO WAY you need 300g to 400g of protein DAILY!