I know that even if you try to manually delete all of your comments, Reddit figures it out and then stops showing you any of your posts, and acts like they deleted them all. Edit: I went back to check and make sure I am not full of shit. Yep, I managed to get through 3 years of posts before they started acting like my account has zero post history. But anything from 4 years back can be easily found googling the username. I have to admit, going back and reading my post history kind of made be feel like a smart funny guy.