Yeah that 15 pounder was the exception. The thing is (at more that 10 weeks) when you get home every night, the feeder will be empty, and you will have the urge to fill it up to the top...DONT!! they will surround you like starving kids, but dont give in...its for their own good...a 10-15 week old Cornish X will eat as much food as you will give it...and kill itself doing so...even at 1/2 pound feed/bird a day, you will still see lots of fat under the skin (esp the hens), therefore showing they were not under-nourished. But you are risking chickens going any longer than 10 weeks and definitely not getting the same feed to meat weight ratio that starts tapering off at 10 weeks...but the meat will still be delicious and huge (that 15 pounder... we ate some that night and made sandwiches with it for at least 3 more days). I use Purina Flock-Raiser as rations at all times..