Actually it is a useful thought experiment because it cuts to the heart of the problem. You 'temporarily' reduce the effective mass of something. So understanding how that is, or is not, possible lets you follow the rest of his reasoning. (on the record, I'm not sure I buy the variable mass argument).
That said, and I've suggested this before. The minimally sized mechanism is well within the mass capacity as a 'ride along' on a Space-X resupply flight to the ISS. Put it up in orbit and have it move itself to Geosyncrhronous orbit without fuel. Nobody would argue about the physics after that.
That said, and I've suggested this before. The minimally sized mechanism is well within the mass capacity as a 'ride along' on a Space-X resupply flight to the ISS. Put it up in orbit and have it move itself to Geosyncrhronous orbit without fuel. Nobody would argue about the physics after that.