I thought the whole reason NASA's shuttles jettisoned their rockets and large fuel tank was because getting that added weight in to space was prohibitive. How is it that they propose to get not only the entire rocket in to space but also enough fuel to provide a soft landing on re-entry of all 3 pieces? I realize rocket tech has come a long way since the Shuttle's design, but is it really that much further along?
Not an expert on this subject, but the landing phase requires much less fuel than take-off. You only need to slow the craft and during the final approach use fine grain thrusters to maintain control.
It requires less fuel because air friction works with you during deceleration, not against you, and because, by the time you do the landing, the craft weighs a lot less, not because you only need to slow down.
I think the video left out a lot of the dull part of aero breaking, making it look as if all breaking was done on rocket power.
I do not see how this would be cheaper and safer than just using a disposable run-of-the-mill steel pipe as main engine (yes, that is exaggerating), but they must have done the math.
I really do hope they can pull it off though!