My juniors, though, are reading Chronicle of a Death Foretold, which forces the reader to consider the abundance of choices that are significant only in retrospect--so although counterfactuals still make for bad lit crit, they're a little less obnoxious. Here's what I had my students do to prime their thinking about the text.
First, list ten successive choices you made between waking and coming to class today.Some of my students immediately complained, "I can't think of more than four choices." I'd respond, "Oh, really? What did you have for breakfast? Eggs? No? Well, what if you had--and you picked the unlucky salmonella egg? Where would you be now?"
Then, write an alternate history of your day, given that one of those choices was made differently.
In fact, when you try to list even ten choices, you start to realize just how many decisions you take for granted, never appreciating their significance because "nothing" happened as a result.