I bought this after reading tons of extremely positive and exciting reviews by other readers somewhere else. I spent 3-4 hours yesterday preparing the basic sauce (the "secret"), and tonight I first cooked the chicken and then the actual curry (a Tikka Masala), always following the instructions to the letter. At first, it tasted a bit bland and quite disappointing. After a while, it tasted terribly greasy and we could not even finish it. What a disappointment!
I am not giving it less than three stars because I think it is fair give it the benefit of the doubt: a majority of readers are really happy with it and I have only cooked one of the curries. However, taking into account most of them are based on the same "secret" sauce, I would not expect much from any of the recipes. So three stars for the book, but none for the terrible Tikka Masala I spent so much time on. Definitely not worth the effort in my experience.