You’ve brought in moral realism, which isnt relevant.
“Would you do X, if it was epistemically rational, but not instrumentally rational”
“Would you do Y if it was instrumentally rational, but not epistemically rational”
If two concepts arent the same under all possible circumstances, they aren’t the same concept. Hypotheticals are an appropriate way of determining that.
You’ve brought in moral realism, which isnt relevant.
“Would you do X, if it was epistemically rational, but not instrumentally rational”
“Would you do Y if it was instrumentally rational, but not epistemically rational”
If two concepts arent the same under all possible circumstances, they aren’t the same concept. Hypotheticals are an appropriate way of determining that.