I said it is a problem, a potential bias that needs be to countered. It was not my intention to suggest that one shouldn't learn about unethical persuasion techniques or the like. I actually ordered the book.

A few times I was accused of, and saw people on LW accusing others of using some kind of 'forbidden' rhetoric against them while I never even heard about such a technique before and which I was sure the person who has been accused never intended to deploy deliberately. This shines a bad light on people who have been accused. The right way would be to kindly remind them of the shortcomings of their argument or that their style of response might be harmful in a discussion with the purpose of dissolving confusion, refining rationality or understanding disagreement.