First off this is two separate questions. 1. Is it fair to employ logical fallacies? 2. Is it ethical to employ logical fallacies?
In a course that I previously took centered entirely around debating, one of the works we read said that if you feel a logical fallacy will help you win in your current debate, and you are ok with the risk of it being called out, then you should use it. So to make this a little simpler, lets say that you have an opponent in a debate who you know doesn't understand what a false equivalency is or that it is a logical fallacy and would without a doubt consider it as logical, is it fair/ethical to use that fallacy to win your debate? I can assume some might say no to this because it could make you appear weaker in future arguments, but lets say this was contained within this single argument that can't be brought up at a later time.