“A starship built around a single massive engine designed to suck in interstellar hydrogen and use it for reaction mass. Because it didn’t have to carry its own fuel around, it could go almost as fast as it liked, right up to the edge of light-speed.”
In “The Prefect” by Alastair Reynolds
So you're happy about a 900-year old alien driving a ship that looks like a police box that can travel through time and is larger on the inside than on the outside towing an entire planet across the universe, but some people are annoyed because it didn't shake enough? Seriously, I can never understand why SF readers get so picky over the stuff they are prepared to suspend their disbelief over. Either you're going to reject the whole damn thing, or you should accept it all, I say. Having said that, while accepting the initial fantastic premises of this book, I'm happy for it to bend basic physics, but not to slit its throat and urinate on the corpse. To take the earth-towing scene again; where's the sense of threat to humanity if, in the end, it can survive cataclysmic events like being pulled across the universe, with only basic refurbishing needed? The basic rule of thumb about suspension of disbelief applies to all fiction, not just SF: anything is acceptable as a premise, but once the premise is in place, you have to follow through as realistically as possible. In other words, you start with a “What If”..., and the “What If” can be completely insane - e.g. What If the CIA invented a non-existent agent to distract the KGB, and then the KGB mistook a real person for that agent. But once you established the crazy “What If”, you can't just add other bits of craziness to get your hero out of tricky situations. Though this is madness, yet there is method in it, and Reynolds is the absolute master of the form. What else? Ah yes. It’s oversaturated with all kind of fancy stuff.