The trouble with "push the fat man" answers is that in the long run they don't result in a world with more people saved from runaway trains, just a world in which fat men no longer feel safe walking near train tracks. The same applies to "I am morally required to jump" answers. Replace "in the long run" with "in the short run" if you are short-sighted enough to pre-announce your answer, as we're doing in this thread; the average fat man and/or morally shameable man is probably capable of figuring out the implications.

Your potential victims may not be Omega, but they may still be capable of figuring out when you're planning to two-box.