We tend to think of Red John as a serial killer, who also has a cult of followers associated with him. What if that's backward from the way we *should* be looking at him?
What if we should think of him primarily as a cult leader, who also has a string of killings associated with him?
Is it possible that Red John is more puppet master than slasher? What if the killings (or most of the killings), and the other "legwork" involved in being Red John (possibly including things like having a relationship with Rosalind Harker or visiting Sophie Miller), are actually carried out by his "disciples" (via manipulation, coercion, enticement, or even hypnosis)?
I think this scenario has the advantages of both the "Red John is a group" and the "Red John is one person" theories. Yes, a group is involved in "being" Red John -- and actually, that's something we've all pretty much accepted, but maybe just stopped short of thinking that the underlings could have been the ones performing the killings themselves (in at least some cases). But only one person is the one calling the shots. Only one person is "really" Red John.
So maybe (for example) Timothy Carter could tell Patrick what his wife and daughter smelled like, because maybe Carter was the person who actually killed them, but did so under the control of Red John. Perhaps he was Red John's "murder weapon," if you will.
When you think of it in this light, many of the supporting details for some of the other suspects fade away (age, height, etc.), and Bret Stiles starts looking an awful lot more feasible. He certainly has the money to fund such an operation, and knowledge of the mental manipulation and domination required to carry it out...
