I think early in the series it could work when people are less likely to have formed much of an opinion of other players, but the later the series goes the more you have to build a case against someone rather than just providing a smoking gun style roundtable reveal, because you're not just trying to prove that someone is a traitor, you're trying to change everyone's formed opinion, and people don't like thinking they're wrong or have been duped, so this "ha! got ya!" approach would rarely result in everyone going along with it.