No expert here, but just want to raise some issues to chew on.
Decades ago I took an ag econ class that ruined me, as everything was discussed as output PER UNIT OF INPUT. So when someone tells me how big a calf their cow raised I'm not impressed, as I don't know how much feed she consumed.
Kind of like people who tell me how much they won at the casino, but won't tell me how much they had to lose to get there. Or someone telling me how far they went on a tank of gas, but won't tell me how big the tank is.
Anyway, I see the expression, "easy fleshing", and wonder what that means. If a cow is "easy fleshing" by eating twice as much as the "hard doer", doesn't sound like easy fleshing to me. Seems a better term would be "big eater", like a lot of "easy fleshing" people I know.
Anyway, if one selects cows just because they are in good flesh, its possible one is selecting for big appetites, which is not efficiency. Efficiency is units of production PER UNIT OF INPUT.
I have two heifers, so watch them closely. Most tell me how good looking my "easy fleshing" one is, but unfortunately I know that she eats a lot more than the other one. Most people throw feed to a herd and don't know how much each cow is eating.
Cows with more muscle eat more than others, as muscle tissue is more metabolically active, so demands more calories to maintain. They may look more easy fleshing, but have to eat more.
Now I realize a cow needs to pass some muscling genetics to her calf so she would also have some muscle, but cows with less muscle are not all bad, as they will eat less.
And of course, a cow's fertility will decline if they aren't eating well enough, so they have to have sufficient appetite for that. But seems if a thinner cow can still get pregnant and raise a decent calf on less feed, that would be good.
As I've posted before, they are finally doing research on cow efficiency and finding significant differences between cows:
http://www.youtube.com/watch?v=_6hSQMz8hyo