Re: Modular versus non-modular
What "they" failed to tell you is that all of the planned LOP-G (formerly Deep Space Gateway) components (there are 4 so far) have a mass of 10 tons or less (the first is 8-9 tons). The Falcon Heavy should be completely capable of flying these components to trans-Lunar injection orbit. What it won't be able to do is fly a manned crew capsule at the same time as the components, since SpaceX doesn't plan to human-rate Falcon Heavy, just Falcon 9 and BFR. Flying a Falcon 9 + Falcon Heavy is still about 5-15% of the cost of an SLS flight.
NASA's man managed to deceive some people with cheap justifications for the SLS. The components can fly on Falcon Heavy, and if the SLS program faces any more delays (maiden flight likely delayed to 2020, manned flight to 2022 if not later), it's possible that crew could fly on BFR.
Biting the hand that feeds IT
