Note, too, this little nugget:
McConnell envisions space coaches cruising around the solar system, each individual vehicle fueling up with water in low-Earth orbit when the need arises. In the future, fuel could be sourced along a space coach's travels — for example, water could be mined from an asteroid or a Martian moon.
Yup .... all you've got to do, is just pop out of that interplanetary trajectory, down into Low Earth Orbit; or, into the orbit of an asteroid or a Martian moon.....
How? Does our author understand the orbital mechanics of his "simple" solution?
Chances are the author doesn't understand the issues. To keep the system going they will have to boost the reaction mass to match orbit with the spacecraft.
Recently read a science fiction book which described a similar concept, but I forget what the drive system was. May have been solar powered ion drive. That author called them cyclers with three cyclers continually cycling between Earth and Mars.
Done right, once the cycle is going the system won't require a lot of additional delta v. Shuttle craft would be required to boost cargo and consumables to matching orbits, but the cyclers themselves would be very efficient.