Prancer you are right. And if you eat out it can be very hard to stick to the diet in its strictest form. I started the autoimmune protocol over a week ago. However I have been adapting it a bit. The idea seems to be to eat just foods that are the least likely to cause inflammation and restricts you to foods unlikely to cause inflammation in anyone - though everyone will, I think, have other foods they can eat without problems, this will vary from person to person. Supposedly when you start feeling better you can start adding other foods in and identify problem foods if you seem to react to any when you add them back in.
I took the plunge and went straight into the strict diet. I felt pretty rubbish - weirdly light headed, hungry, low energy. I felt I needed carbs. In hindsight, it is probably more sensible to transition into the diet than make a sudden change as otherwise you are effectively asking your body to change its gut flora instantly and change the way it metabolises food (more fats for energy than carbs?) to make best use of the new diet. After a few days feeling bad on the diet, I added in rice (I've been doing quite a bit of exercise and felt deprived of the right fuel). This improved things (and I don't believe I have a problem with rice whereas I have some suspicions about wheat). Soon after I added in nuts and seeds and felt better again (in particular I added brazil nuts - perhaps I was lacking selenium otherwise but that is pure speculation). With the addition of nuts, seeds and rice the diet has been easier. Basically though its eating only fresh ingredients, no processed foods, no sugary foods, generally no grains (but rice at the moment for me) and no legumes or 'nightshade vegetables' (tomatoes, potatoes, some peppers - black pepper supposedly ok), no dairy.
Today I have had a bowl of oats which is a definite no no on the diet. I have started keeping a food diary so will see if there are any noticeable effects. I know I should give the pure diet longer in theory but I honestly don't think it was doing me any good. I've heard even gastroenterologists say that we don't really understand the gut and all its complexities. Its naive to assume that the same diet can help everyone and everyone should do things a certain way. Tolerance to different foods varies so much through the population. You have to find what works for you (if diet is the solution at all).
Its too early to say if the diet is helping my fingers - it seems it could be but I can't definitely say. If it is the case (and I'll find out for sure if I have arthritis in my fingers very soon), its possible that cutting out dairy has made the difference - there is evidence that this has worked for others with arthritis. Obviously arthritis isn't POIS but it is thought to be (at least in some forms) autoimmune and so what helps one autoimmune condition might, I suppose, help another (if indeed there is any autoimmune issue underlying POIS). There is also evidence that at least for some people (and it does seem to vary a lot) that cutting out nightshade vegetables can help a bit with arthritis. However, the easiest to find (on the internet at least) scientific studies on diet and arthritis are to do with fasting followed by a vegetarian/ vegan diet and this has been shown to help some people. Some people (I've not seen any papers on this) have reported improvement in arthritis with paleo though - very different to vegan diet!! - though both no dairy.
I decided to read up on WHY certain foods are excluded from autoimmune protocol diet and other supposedly helpful diets. Based on that and listening to my own body I am trying to find my own way.
I mentioned I have started to keep a food diary. I have tried this with pen and paper before - I was never able to maintain it. However, I downloaded an app for my phone for this purpose and it is proving a much much better way to record what I eat and how I am feeling. The app I use is this one (there are others available for iPhone etc):
https://play.google.com/store/apps/details?id=com.geoffholden.android.fooddiary&hl=en_GB