My apologies if this doesn't deserve a Discussion post, but if this hasn't been addresed anywhere than it's clearly an important issue.
There have been many defences of consequentialism against deontology, including quite a few on this site. What I haven't seen, however, is any demonstration of how deontology is incompatible with the ideas in Elizier's Metaethics sequence- as far as I can tell, a deontologist could agree with just about everything in the Sequences.
Said deontologist would argue that, to the extent a human universial morality can exist through generalised moral instincts, said instincts tend to be deontological (as supported through scientific studies- a study of the trolley dilemna v.s the 'fat man' variant showed that people would divert the trolley but not push the fat man). This would be their argument against the consequentialist, who they could accuse of wanting a consequentialist system and ignoring the moral instincts at the basis of their own speculations.
I'm not completely sure about this, but figure it an important enough misunderstanding if I indeed misunderstood to deserve clearing up.
I dispute the claim that the default human view is deontological. People show a tendency to prefer to apply simple, universal rules to small scale individual interactions. However, they are willing to make exceptions when the consequences are grave (few agree with Kant that it's wrong to lie to try to save a life). Further, they are generally in favor of deciding large scale issues of public policy on the basis of something more like calculation of consequences. That's exactly what a sensible consequentialist will do. Due to biases and limited information, calculating consequences is a costly and unreliable method of navigating everyday moral situations; it is much more reliable to try to consistently follow rules that usually produce good consequences. Still, sometimes the consequences are dramatic and obvious enough to provide reason to disregard one of the rules. Further, it is rarely clear how to apply our simple rules to the complexities of public policy, and the greater stakes involved justify investing greater resources to get the policy right, by putting in the effort to actually try to figure out the consequences. Thus, I think the evidence as a whole suggests people are really consequentialists; they act like deontologists in small-scale personal decisions because in such decisions deontologists and consequentialists act similarly, not because they are deontologists.
This is not to say that people are perfect consequentialists; I am not particularly confident that people are reliable in figuring out which are the truly exceptional personal cases, or in telling the difference between small scale and large scale cases. But while I think human biases make those judgments (and so some of our moral opinions) unreliable, I think they are best explained by the thesis that we're mostly (highly) fallible consequentialists, rather than the thesis that we're mostly following some other theory. After all, we have plenty of independent evidence that we're highly fallible, so that can hardly be called special pleading.
Presumably you think that in a case like the fat man case, the human somehow mistakenly believes the consequences for pushing the fat man will be worse? In some cases you have a good point, but that's one of the ones where your argument is least plausible.