The 'laws' of Physics change every day, if not more often. Fermi went to the grave not knowing if the electron was indeed the smallest sub-atomic particle; that didn't make him any less of a physicist. Huygens made observations and assumptions based upon them according to what he had to work with at the time. That didn't make him any less of an audio engineer either. If you sincerely think he had it all figured out and there's no room to go beyond what he did, then fine.

I've gone to the trouble of building horns according to Huygen's model and my own, and mine pass high frequencies on the order of two to three octaves higher than the Huygens models do. I feel safe in saying that you haven't done so. When you have ring me up again and we'll compare notes.

If you really must hinge your opinions on art that's at least 20 years old before you'll believe in it take a look as US patent #4790408; I'm not the first to tread this ground, just the latest. If the internet had existed when this was published what I'm saying now would be old news.