Here is my theory. Please read all.
I think CBI Ron is real Robert Kirkland and he is Red John. At the Red Barn, Robert finds his twin brother Michael who tries to get rid of his alcohol issue, but but he becomes a drug addicted now. He is the weaker sibling. Robert kills other members of the Visualise. The problem is now how to prevent the Visualise from killing Michael. The twins switches their identities. Then real Robert disappears and Michael (now Robert) hears no news from his brother. What Michael does not know that his brother had a plastic surgery and changed his face and identity. that is why hi did not kill anybody for a decade. because creating a best fake identity takes years (in one episode an Irish guy who creates fake identities told so). Maybe during these years he killed under different alias like Roy. After a decade, he becomes CBI (R)ed j(O)h(N)
This theory explains many things.
He is there from the beginning.
He is like Waldo.
He is really on the list (Real Robert Kirkland)
He fits the description of Simon Baker.( it is like killing a family member) he is always there.
He is close Jane and the investigation.
Other things
He is mar. He is (M)ichael (A)ka (R)obert
Examine carefully Robert Kirkland (actually Michael). He has self-control issue and shaking hands. He is an old addict. He was desperately looking for Robert. That is why he ask people "do you recognise me?". He wanted to know if they had met Robert. He did not know for sure that Robert is Red John or his tool killed by Red John. He actually brought those people to his own cabin.
Ron had a phone at his hand when Jane came to the CBI at the end of episode one of season six. Then he called his accomplice who killed Partridge and while his accomplice was drawing his mark on Lisbon's face, he spoke to Jane through his accomplice' and Lisbon's phones. He kept it short because he did not want Jane to understand he was talking to him through two phones. In this way, he also eliminates himself as a Red John suspect in the eye of Patrick and many viewers.
When Tyger Tyger killed his brother, he gave tattoo clue to Jane to led him to kill the group members who are also Red John suspects (Bertram, McAllister and Smith). He likes Jane killing people and drawing him into darkness.
After the loss of his brother and cleaning in the California Law Enforcement, he will desperately seek the friendship of Jane. then, bang! Bang!
What do you think?
Sorry for bad English