Found mathgainer's stats: 6ft tall and 165lbs. So, essentially a famine victim. Scaling back not required.
Looked through a couple of his threads and only found he was trying to work his way up to GOMAD and made a specious argument that Pound of Beef a Day was more manly or some such rot.
Beef is probably better than milk as others have said. I just think for any human male who trains and that is not a midget, a pound of beef a day is essentially a snack.
People complain of being "hard-gainers" and lifts not improving -- root cause is usually eating like a Jr High cheerleader or this gal:
Girl Dinner | Know Your Meme