Does Musk have anything more than simple talk for this idea?
It does not matter. You look at the physics and get the answer, period.
The physics of fluids in motion is incomplete because of the variety of characteristics that fluids can hold.
However, a compressible fluid can be a shock absorber because of its elasticity and compressibility... at least until it is compressed so firmly that it starts to lose its fluidity. This suggests that the shock of atmospheric change as it flows around the vehicle will be absorbed by the cushion of steam. Because of the rapid movement of the vehicle, the shock will be past the falling vehicle before the steam cushion can transmit the shock to the vehicle itself.
Does Musk have reliable data about this? Is the data only simulations? Or did he manage to do some actual tests somewhere along the line?
