[Straight Vermonter]

The problem is that cows typically do not graze in herds. Some farmers are employing mob grazing to simulate the benefit of herds. As to cow flatulence the carbon that is in the grass is going to be converted into CO2, either by the grazers or by bacteria. It really doesn't matter which one.

[familyop]

"The problem is that cows typically do not graze in herds."

Cattle do everything in herds. The bulls lead, warn the herds against predators and find water. It's obvious to real farmers in the Midwest and more obvious in large grazing areas of the West.