Engineers and inventors have an unfortunate tendency of getting entrenched in controversies. It is certainly wonderful to be able to say "I told you so", and to feel more clever than the rest. I am no stranger to this kind of behaviour. However, I do try to stay polite and, somewhat unusually, go the extra mile to convince others within their own frame of reference, instead of insisting on a "better" way of seeing things.
There are two levels of controversy in aerodynamics. The one is about pet design features. The other is of a more basic nature.
The first items in the list are quite basic in nature. Still, these are the ones that cause the most heated, and the most unnecessary arguments. The first one is about the supposed difference between Newton and Bernoulli, including the "equal path" fallacy. The other is the eternal tiff about the infamous "downwind turn" syndrome.
The rest of the list gives discussions of what I consider to be erroneous aircraft design ideas, like the canard and to a lesser degree, the T‑tail. I also tackle an almost universal, but flawed interpretation of the wing aspect ratio, which has led many people who should have known better, astray in their designs.