[MBCook]

Yes. I believe the idea is to get the rocket up to where the atmosphere is extremely thin so you don’t need much fuel to complete the journey. The hard part of the initial acceleration through the thick atmosphere which burns most of the fuel is bypassed.

[IshKebab]

But on the other hand you add a lot of mass to deal with the air heating and increased structural loads. Will be interesting to see if it ends up being worth it.

I'm mostly curious how they deal with the sudden change in load on the spinner.