Re: "You can do it in a lot less time than that, providing you start out with enough thrust. "
Could you boost this with intermediate fuelling points along the way? I know there is one case study that calls for refuelling close to the moon using libration (Lagrangian?) points to maintain a stable position. What about using something like that to minimise the main vehicle launch payload - i.e. to send a number of rockets up and then assemble them in space.
For those who voted for Donald Trump to be the 100th passenger - what would the other 99 have done to deserve that?