I enjoyed this book but it did confirm my opinion that le Carre is an overrated writer. I pretty much new how the book was going to turn out from almost the beginning. Le Carre, at least in the novels that I have read, perhaps it is different with his later stuff, becomes predictable once you are used to him. It itself predictability is not bad, but le Carre has a habit of presenting as a surprise things that you see coming.
If le Carre wanted to surprise me, he would present a spying operation where every thing went according to plan and no one betrayed anyone, and everyone was a decent person acting for the right reasons. I don't mind pessimism, but le Carre feels a bit like a one trick pony. Having said that, the book was enjoyable and le Carre often writes prose very well. I certainly intend to read more, but he's not a great writer or as clever as everyone seems to think.