Heh, foremost, I work in video production and we have a lot more displays around than your average consumer that is posting in this thread. I mean no offense in saying that or to question your credentials.
That said, pretending that "retention" and "burn-in" are unrelated terms as you did to imply I am not well-versed in this subject is misleading. I clearly stated different TVs have different susceptibility to retention, whichto me, and I don't mean to go inside baseball on you hereimplies that some TVs have very little to no retention, and some have such an issue with retention that it becomes burn-in. Images that become "burned in" are first at a stage of retention; a point that could, reasonably and usually, be mostly cleared if proper steps are taken at the right time.
If you meant to say "burn in is permanent and does not happen on OLED displays", you could not be more wrong. Simply because burn-in is less common now with OLED than with Plasma does not mean it does not happen, because it can, does, and will. In fact, there are people not just in this thread but on this very page of this thread reporting as much.
And yes, I do have an OLED TV. And, I would wager off-hand that I've used, calibrated, and tested more OLED TVs than you've actually seen in person. Given you cannot admit or don't understand that OLED is susceptible not just to retention but burn-in, that wager's looking pretty safe.