I've been thinking a lot. People keep forgetting about one very important person. Michael Kirkland (Bob's twin brother).
We know that Michael Kirkland uses Bob Kirkland's ID (when he killed the guy in the hospital). And Bob Kirkland said that they both had a rough childhood, and someone "helped" Michael, taking him into some cult, etc. Bob thought that Red John was the one that took Michael but when I think of it, it could have been Brett Stiles. We know RJ was in visualize, so I'm guessing Brett Stiles took Michael, "visualized" him and Michael became Red John. They have all those blood rituals in Visualize. And makes sense because Bruno Heller keeps saying it's someone from the list. Michael is, in a way, in the list, being Bob's twin. The only three guys with voices similar to Red John are Brett Partridge, and he's dead, and the twin Kirklands, and one of them is dead. Makes perfect sense if it is Michael Kirkland, and it would still surprise everyone.
Do you guys agree? Think about it, makes a lot of sense.