The point of patent protection is that you teach everyone how to build the thing that's being protected, in exchange for a monopoly.

Not actually teaching people how to build the thing that's being protected, but still having a monopoly on it is the worst of all worlds.

If you aren't going to teach us how to build something, don't expect patent protection for it. I'd rather you keep it as a trade secret, good, go do it, it's a free country, but then we can just reverse engineer it. If I don't have an NDA with you, I have no reason to keep your trade secret... secret.