I found the description of fats confusing, especially in the newer literature like the tri-fold food plan, where the only list of fats included is the maintenance list of fats.
My sponsor finaly told me, after the first 30 days, I could use 1 tsp of any of the fats that would be measured by a teaspoon - so I could have 1 tsp of mayo, or 1 tsp of butter (before reaching maintenance). She did not say I could add the foods that equal a fat though (olives, avocado, etc).
Hope that helps too, because this was something I found really confusing - I thought the only fat I could have was oil for a long time! It was nice to be able to vary it finally.