That's interesting in theory, but as far as I know our interstellar propulsion technology hasn't advanced significantly at all in the last 50+ years. You can't do theory in a vacuum forever. I'd argue that unless we launch an interstellar something, we're never going to see any technological advances in the field.

The wait calculation implies that the returns from economic growth will eventually be converted into rocket fuel. A fun equation, but economics doesn’t translate well on time scales where depreciation of capital is 100% and becomes another expense.

Hey, I like that idea.

Maybe it implies that every interstellar mission is just an in-flight rescue mission.