Reed Diamond as Ray Haffner made the PERFECT Red John.
I guess the writers forgot that Red John was Ray Haffner because they wrote the Red John episode with the wrong ending.
This reminds me in some ways of the movie, The Usual Suspects where Gabriel Byrne thought he was Kaiser Soze until the movie came out and he was upset that Kevin Spacey turned out to be Kaiser. Not exactly the same thing but you get the gist. ;)
Ray Haffner IS Red John. Thank you Reed for a PHENOMENAL performance in The Mentalist. You are missed already.