Agree with him about the inefficiency of killing animals for their protein. Some (farmers, etc, to some extent) disagree with him about the effect of grazing on the landscape. I read an article recently giving as an example an area that was blocked from grazing to protect rare plants: apparently the plants that grew up when ungrazed killed off the plants that they sought to protect. On the other hand, factory farming is even worse.
@brthrphl I don't know, I find a lot of his arguments and evidence about the environmental damage that grazing does to be quite convincing. In his book 'Feral' there is a lot of detail about the impact of sheep farming in particular and the benefits to the habitat of re-wilding large areas.
Yes, he does make some convincing arguments, and at least some of those in the other camp have a vested interest. Might sit down and have a look some time. It would be a good place to start looking at both sides of an issue and trying to figure out what evidence there is and what it actually says.