I also just conducted a N = 1 study to support my argument. The result was mixed. The test subject started out supporting your point of view with strong emphasize on personal preferences and the claim that several repetitions of the experiment, i.e. traveling back in time a few minutes after a choice between steak and fish was made, would always yield the same choice. The response changed when I asked for simply choosing between two arbitrary numbers, 5485151218 or 1584512548, stating that repeated experiments would yield each choice with equal probability.

So the subject generally put strong emphasize on his personal history and preferences as well as on the circumstances and consequences of the decision. But if those considerations were eliminate by asking to make inconsequential decisions where the subject could hardly have any preferences, then the aspect of being able to make either choice became visible.

This made me better unterstand where your point of view comes from. In hindsight I have to admit that I unwittingly always heavily focused on inconsequential decisions without preferences. But I would now extend or change my argument and argue that this actually the right thing to do because those are the more interesting cases.

There were several options and I freely choose the one that seemed best to me. The use of freely and choose seems almost a bit paradoxically to me in this case. On the one hand it emphasizes the absence of constraints, probably with most emphasize on external constraints, and the availability of several options, on the other hand it implies that considerations of personal preferences, circumstances, and consequences naturally led to one choice.

So in what sense was the decision free if the choice is dictated by constraints? I can only think of partitioning possible constraints into two groups, those that someone wants to obey and those that one does not want to obey. You want to eat your favorite food but you don't want to be forced to eat some food.

This probably also has ramifications for how one has to look at different options. In what sense are there actually several options if the choice is dictated by constraints? For differing sets of options the choice may differ, but for a fixed set of available options there is only one choice. So it seems to me that the actual choice is between differing sets of available options, not between different options once the set of available options is fixed. But this choice is not a real choice either, the set of available options is fixed with the scenario the agent finds itself in.

Leaving the case behind, were the decisions are heavily dictated by constraint, I will finally return to the case with actual choice. This seems to be the much more interesting case, what if decisions are not dictated by constraints? Could you have chosen otherwise? I still argue that many if not most people would respond yes, of course, I could have done something else. Even if this position is hidden in many scenarios by considerations of constraints that dictate or at least seem to dictate one choice. I could have chosen differently but I would never have done so given the circumstances.