The only two guest stars in the episode titled "Red John" is the actors that play Reede Smith and Gale Bertram. Heller can't already be revealing who Red John is? And is it then one of those? That would be truly boring, especially if it was Reede Smith. Smith is not only the character everyone never thought was Red John but also the character everyone never hoped to be Red John. He's fat, ugly and a lousy actor. I can't really imagine him as RJ. 

Perhaps Heller did as the director of Seven and not revealing all actors in the opening credits, or perhaps "Red John" is not about revealing Red John's identity but rather about his young days. Either way it's in my opinion a really interesting observation. 

What do you think?