This seems to run contrary to basically everything I've read on this topic. For instance during Trump's presidency there was a tremendous amount of fearmongering about him possibly wanting to nuke North Korea. This led to commentary from numerous generals and others opining on the topic about whether they would or would not obey the order. Here's some rando link. [1] The sort of system you're describing would enable the President to unilaterally carry out illegal orders independent of the military. I just find it difficult to imagine that they would concede that, not only because of the power concession, but because of the ethical or even constitutional implications. Notably officers don't swear an oath to their commanding officer or anything of the sort - they swear it to the Constitution.

As for Nixon, he was literally playing the madman as part of a strategic goal [2] (arguably the exact same thing North Korea is doing in modern times), but privately was the one who ultimately scrapped a plan that involved nuking Vietnam. [3] A nice quote from the Madman article (from Nixon), "I call it the Madman Theory, Bob. I want the North Vietnamese to believe I've reached the point where I might do anything to stop the war. We'll just slip the word to them that, "for God's sake, you know Nixon is obsessed about communism. We can't restrain him when he's angry—and he has his hand on the nuclear button" and Ho Chi Minh himself will be in Paris in two days begging for peace."

[1] - https://www.dailymail.co.uk/news/article-5082689/Retired-gen...

[2] - https://en.wikipedia.org/wiki/Madman_theory

[3] - https://en.wikipedia.org/wiki/Duck_Hook