I know of one man who field dressed a deer with a Victorinox Classic. He didn't have his 'real' knife with him, and it was slow and PITA, but it got done. A peanut would be a walk in the park compared.
On the same note, in 1997 when the better half and I were on a 5 week around the country ramble, we stopped at Mesa Verde Natioanl Park, I wanted to tour the old cliff dwellings. I have an interest in archeology, and if I had to live my life over again, I may have went there. But while we were there, I signed up for a demo/lesson in the ancient culture. A park ranger had a rear haunch of antelope that had been killed that morning by a car, and was showing how easy a flake of obsidian could skin and slice meat. He had a large chunk, and with a stick, he used the percussion method to knock off a large single flake of the Obsidian, about an inch and a half to 2 inches long.
That stone flake sliced right through the hide, meat, and tissue like a razor sharp knife. Maybe a bit better! It made a believer out of me on what a small sharp blade can do. Then of course, you have Otzi. His knife is only a 2 inch blade, but he skinned out game and maybe even the bearskin cloak he was wearing. Hours before his death, he was in one heck of a fight, with DNA blood samples from a few different people on his clothing and knife. The knife must have done the job., because he did get away, with an arrow in his back that later was the cause of his death.
A two inch blade will do if the user is up to the job.