IMDB's Owain Yeoman (WAYNE RIGSBY) trivia says :
"Trivia: His heroes are his wife, Lucy Davis, because of her subtlety to acting and Edward Norton because of his ability to change roles, which Owain has said to be what acting is all about"
(Source : http://www.imdb.com/name/nm1466859/?ref_=nv_sr_1)
-Look at Rigsby's initials : W.R -> Can easily be completed by "edJohn" = WRedJohn, the pronunciation doesn't change at all. We have (W)RedJohn, the W is silent.
-If you count the number of letters that contains "RedJohn", you get 7 Letters. There are 7 suspects from the list. From the beginning of season 6, you can see that the first episodes were about identifying each suspect from the list as them being RedJohn or not, approximately each episode is about 1 of the suspects, and moreover we understand that the list wasn't really made up with the real RedJohn, but with some disciples, which we don't care about at all actually.
Logically, on episode 7, the storyline will tell us that the suspects were actually disciples but not RedJohn himself,
the CBS announced that RedJohn's identity will be revealed on episode 8 (Episode named "RedJohn")
If we come back to our W.R "(W)RedJohn" theory : So the 8th episode is named with a 7th letter word? No,
actually it is named with 8 letters, but 1 is invisible : the silent "W", for W.REDJOHN.
This theory can be illustrated with the REAL suspects list, that PJ kept for himself, containing the 7 + 1 Suspect
: Wayne Rigsby.
Thank you for reading, hope you enjoyed (and understood!) my theory :).