> Nothing in your reply now, nor in any of your other comments, supports that claim
Singer's insistence that a utilitarian doctor is morally bound to kill a patient to save others is sufficient.
> Your claim does not follow from the fact that in rare, exceptional cases rule-breaking, perhaps in secret
No perhaps about it, secrecy is part that can only really be discarded in non-iterated settings, in the endgame.
> but such virtues, once habitualized
Of course you know that "habit", contextualized in the moral framework where habitual action is merely instrumental too, is a categorically weaker insurance against rule-breaking than habit plus belief in the principle according to which those habitual decisions are correct generally.
> Do you possess any empirical evidence showing that real world utilitarian adherents are less upholding of everyday norms against lying, stealing, and so on?
Yes, for example the effective altruism movement is comprised of generic totalitarian scum, which is well reflected in their consensus position on AI safety. I notice you flinching from the example of SBF and his little club of Singerians too.
The problem of utilitarianism, however, lies precisely on the margins. It is rational for utilitarians to build up reputation and influence with charities and such nonsense, to then expend it on a massive power-grab. SBF's only fault is that he moved to early, isn't it?
> You haven't described what alternative moral view you yourself adhere to.
Intuitive deontology.
> If the only way to prevent the end of the world and the death of everyone would be to secretly break some everyday rule once
Jaywalking isn't what the "pivotal act" theory entails, and your theory about total death is specious and motivated by the political benefits of such an act.
Moreover, if [you believed that] the only way to prevent the eternal suffering of everyone would be to secretly work towards the extinction of humanity, would you not work on it? A consistent utilitarian would.
> Would that warrant saying that your own view obligates you to have a "fundamentally untrustworthy and conspiratorial mindset"? If not, why not?
Normal people (ie not effective altruists/utilitarians) have ad hoc "decision theories". I am not an exception. Existence of a world is good qualitatively, not as an ultimate expression of the Singerian principle. I believe that lying is wrong qualitatively too, so for me, the logic of habitually being honest applies in the way it cannot apply to a utilitarian, even if you can design a hypothetical where I would have to agree that lying is justified. A world of utilitarians is not a morally good world; a surgeon should commit to losing more lives than otherwise possible in that scenario, because it would not befit a surgeon to kill patients; utilitarian calculations are invalid, so I do not engage in them.
In more contingent terms: habitual, as you put it, utilitarian reasoning leads to justification of your preferred policies via nonsense utility estimates. Proclaim "vulnerable world hypothesis", now anything you'd want is justified by saving the world, and you get to ape the respectable adult too.
It's risible.