I understand why pre-delegation of authority for the release of nuclear weapons to field commanders was seen as necessary by those in the United States government; Daniel Ellsberg has made the argument that it was (or was at least considered) to be an essential part of deterrence, i.e. the Soviets would be deterred from making a 'decapitation' strike against the US political leadership if they knew that doing so would not prevent nuclear retaliation.
But, my understanding of deterrence is that it is a political concept, and one that flows from public signals broadcast to a potential aggressor, and yet: I have long understood that pre-delegation itself was a closely-held secret. Wouldn't pre-delegation have to be publicly announced for it to serve a deterrent role? Or was there some deeper assumption that the Soviets would just "know" (i.e. through espionage or subtle signaling)?
Would love to hear from u/restricteddata if he has the time. :-)
The theoretical understanding of deterrence — which includes signaling — and the practice of US (and Soviet) nuclear forces were always out of whack. (Something lovingly and memorably mocked in Dr. Strangelove: "The whole point of the doomsday machine...is lost if you keep it a secret!") Especially with the Soviets, as the US did publicize its weapons systems (heavily!) even if it kept the specific capabilities secret. Questions of doctrine though were always kept very close by the United States other than broad ideas (e.g. the floating of the "no-cities" policy).
Predelegation is an interesting case study in this, one I haven't looked into closely but really ought to as part of my next project (which is on Presidential control of nuclear weapons). It fits into a rather tricky place. In principle, yes, you'd want the Soviets to know what decapitation attacks would not be successful in preventing response, and thus you'd deter them. In practice, the idea that low-level military officers had the ability to use their judgment to launch nuclear attacks would be politically very problematic: the safety and security of the US approach relies on the idea that unauthorized attacks would be impossible, and since World War II it was an article of faith that the personage of the US President was ultimately the only one who could give that order. Even into the 1970s, when Eisenhower-era predelegation was finally admitted to in public by the USAF, its extent was heavily underemphasized under sworn testimony to Congress (whether out of ignorance or deception, I don't know).
(Dr. Strangelove, again, gives a nice peek into the public feelings on this: the entire movie a reaction to fears of an unauthorized nuclear war, of a "rogue general." These were not idle ideas; by the Kennedy administration, even McNamara and JFK were worried about such things and took steps to decrease the possibility.)
Anyway — this is a good question. I have never seen anything that indicated that the US planners were worried about the lack of signaling in this instance (or any, to be honest; again, this level of deterrence theory, while popular among academics and think tanks, seems to have had minimal impact on actual planning in the military, and blatantly ignored by Presidents). The overriding concerns were things like making our doctrine too transparent would encourage the Soviets do try and countermand our command and control systems, or fears that too much information about it would make the American people or our NATO allies very uncomfortable. There's a definite tension in particular on predelegation (that doesn't exist for, say, submarine second-strike capabilities) because of the political angles.