ideologically permaculture and monoculture are opposed, but there are positive ways to grow food in large areas that promote permanence by building soil, organic matter, nutrients and retaining water etc...
I personally don't see the issue in combining two healthy systems if there are no other choices. Permaculture is not a religion thats perfect in every way, it's a set of (very important) tools that can be used on different areas to varying degrees of 'perfection'.
I have a 20acre yard with a permaculture system full of veggies, fruits, nuts, animals and forest... but I also have 600 acres of land that I simply cannot do full permaculture on. BUT, through no-till, intercropping, rotation with grazing, green and compost manuring, and no use of chemicals I am able to make a Positive contribution to an otherwise negative situation. If I could set aside an area to grow vegetables just for oil/fuel that would be even better!
that's my two-cents!
