Not the parent poster, but I'll barge in and say I don't have any. Who knows, though - maybe there are actually some really good ones, and I'll never know them

Not the parent poster, but I'll barge in and say I don't have any. Who knows, though - maybe there are actually some really good ones, and I'll never know them because everyone who came up with one kept quiet lest they be blacklisted and hounded out of polite society. Human reasoning is a cooperative effort (when can you say have you last won a debate on a topic widely regarded as important using only arguments you came up with yourself in a vacuum?); if you expel a position from the commons, you tilt the playing field against it in a way that is orthogonal to its truthfulness, and thereby destroy what would otherwise be a useful correlation between how a position fares in the debate circuit and how likely it is to be true.