Indeed I agree that it is possible, and probably desirable, to phrase the argument less bluntly than I did. However, it seems to me that submitter B is arguing against making such arguments at all, not arguing to make them in a more polite fashion.

Furthermore, here of all places, "If you (think you) posses evidence that I do not, show it and update me!" should be a background assumption, not something that needs to be put as a disclaimer on any potentially-controversial statement.