It is funny how the pendulum swings. My fast days were extremely easy in the first couple of weeks and the non-fast were hard (either because I didn't eat enough or because I pigged out because I could), then the fast days got hard and the non-fast easy. Now that I am about 5 weeks in, both are pretty easy, and certainly much easier than anything else I have ever done.
Paula, I would NOT mess with the non-fast days given your Coumaden issues. Like I said you could always start with the BPC in the morning and that out to boost calories and mood and prime the pump so to speak for nutrition through out the day.
I will say that JUDDD was very hard for me because of the rigidity of the fast days being every other day, and 4:3 was hard because of the frequency of the fast days. It may be that I will lose slower on 5:2, but it is exponentially easier than either of the other methods and allows me to feel normal with regards to eating without worrying about putting on weight. Well, and technically I am doing 3:2:2 (3 non-fast/normal: 2 moderate calorie/eating window :2 "fast")