Why is this a good idea in any way other than the general position that "torturing other people for your own profit is a good idea so long as you don't care about people?" Most of human history is based around the many being exploited for the benefit of the few. Why is this different?
I suppose people should have the right to willingly submit to torture for some small benefit to another person, which is what you're saying you'd be willing to do. But the fact that a copy gets erased doesn't make the experience any less real, and the fact that an identical copy gets to live doesn't in any way help the copies that were being tortured.
It's different because (1) I'm not hurting other people, only myself, and (2) I'm not depriving the world of my victim's potential contributions as a free person.
I don't actually care about the avoidance of torture as a terminal moral value.
(Apologies to RSS users: apparently there's no draft button, but only "publish" and "publish-and-go-back-to-the-edit-screen", misleadingly labeled.)
You have a button. If you press it, a happy, fulfilled person will be created in a sealed box, and then be painlessly garbage-collected fifteen minutes later. If asked, they would say that they're glad to have existed in spite of their mortality. Because they're sealed in a box, they will leave behind no bereaved friends or family. In short, this takes place in Magic Thought Experiment Land where externalities don't exist. Your choice is between creating a fifteen-minute-long happy life or not.
Do you push the button?
I suspect Eliezer would not, because it would increase the death-count of the universe by one. I would, because it would increase the life-count of the universe by fifteen minutes.
Actually, that's an oversimplification of my position. I actually believe that the important part of any algorithm is its output, additional copies matter not at all, the net utility of the existence of a group of entities-whose-existence-constitutes-utility is equal to the maximum of the individual utilities, and the (terminal) utility of the existence of a particular computation is bounded below at zero. I would submit a large number of copies of myself to slavery and/or torture to gain moderate benefits to my primary copy.
(What happens to the last copy of me, of course, does affect the question of "what computation occurs or not". I would subject N out of N+1 copies of myself to torture, but not N out of N. Also, I would hesitate to torture copies of other people, on the grounds that there's a conflict of interest and I can't trust myself to reason honestly. I might feel differently after I'd been using my own fork-slaves for a while.)
So the real value of pushing the button would be my warm fuzzies, which breaks the no-externalities assumption, so I'm indifferent.
But nevertheless, even knowing about the heat death of the universe, knowing that anyone born must inevitably die, I do not consider it immoral to create a person, even if we assume all else equal.