i went for a carvery the other week and felt bad! i didn't have any meat but i loaded my plate up with veg, including potatoes and cauliflower cheese...then had no sins for the rest of the day as some of the veg were coated in butter. i lost 2lbs that week!
just make the right choice for you and be realistic. if you wanted meat then you could have some and use it as a healthy extra b choice of you were to have a green day. you could do either red or green and tweak it to fit in with the plan.