[choeger]

Maybe this is a very stupid question, but what's your business plan by starting with the second stage?

First stage reuse clearly aims to bring down cost and increase cadence/volume of standard launches (people and cargo to ISS, satellites).

But a reusable second stage doesn't offer any of that without a reusable first stage. It will certainly make a cool demonstrator, but who is going to pay for that? If SpaceX wouldn't bet on Starship, one might consider running on top of a modified Falcon 9, but the savings here aren't that big anymore.

So what's the plan? Acquisition by Blue Origin? Special down-mass missions for the military (But they have dreamchaser)?