Second, on the madly bogus science, take a deep breath and remember that this is Doctor Who, where a box can vanish from one physical location and reappear in another, laws of conservation of mass be damned. I was in high school when Full Circle came out, and when Tom Baker said “definitely morphologically similar karyotypes”, I nearly switched my grade 13 credits to include biology because I had no idea what it meant but it sounded cool. And yes, Capaldi did mispronounce “prokaryotic” as “prokoryatic”. (See “The reason I’m writin’ / Is how to say chitin” for handwaving about a similar gaffe from Pertwee.) But so what?
The moon wouldn’t actually gain 1.3 billion tonnes in mass as it got ready to hatch, causing the higher tides and natural disasters? Check. Apparently, in real science, it would lose 15% or so of its mass before hatching. Of course, this implies a warm and well-ventilated incubator, not a near-vacuum. And it would further imply that Doctor Who is trying to be science-fact, and not using science-fiction trappings to provide verisimilitude to a fairy tale. On which grounds, I’m not going to say anything more about the madly implausible single-celled organisms that end up looking like (and spinning webs like) spiders. They aren’t the point.
Clara asks the world what they think should be done and then ignores what they say? Not bothered by that either. (Part of that may be pesky facts eclipsing the fairy tale: given all the natural disasters, who is to say how many people actually saw Clara’s broadcast, or changed their lights for that reason? The lights turning off in visible-from-the-moon blocks are more likely to be power companies turning off, or losing to natural disasters, whole sections of the grid at once.) But even if we allow the fairy tale that Clara asked and the result from the bits of the world that she could see was what those people thought, it doesn’t absolve her from making the best decision she knows how to in that moment. She is perfectly able to make a different decision, so long as she can live with the results. It feels like a rebuttal to the unanimous referendums of The Beast Below – and who else wonders if the “unique” Moonite isn’t also the last of the Star Whales? (And don’t get me started on the “science” of that episode.)
One thing that did bother me was the Doctor leaving the three humans to make up their own minds. The Doctor feeling that the decision was too important for humankind not to make without his interference, totally fine. But on the Day of the Doctor, another day where the whole path of a civilization was decided, Clara didn’t leave the three Doctors alone because the decision was one that Gallifreyans had to make without interference. Clara inadvertently changed the future of everything just be reminding the Doctor to be himself… “Then what do I do?” / “What you’ve always done. Be a Doctor.” It seems a big thing for the Doctor to forget. It seems the sort of thing he ought to have remembered before making the quip about it being time to take the stabilizers off Clara’s bike. Lundvik’s “What a prat” was well earned.
Another thing that bothered me was Clara’s later outburst at the Doctor. Of course there should have been an outburst, between the fear that she might have gotten it wrong and the anger that the Doctor left her to make the decision on her own. But “Don’t you dare lump me in with the rest of the little humans that you think are so tiny and silly and predictable” doesn’t feel like it belongs in the same universe as “Blimey, that’s amazing. Do you know in nine hundred years of time and space I’ve never met anyone who wasn’t important before.” The same universe as Waters of Mars Ten, who (infamously) did divide people into important people and little people, maybe. But as Eleven he grew out of that. For the “officer” shot from The Caretaker to have been so effective he must as Twelve have moved some way back. The nine hundred years on Trenzalore from Time of the Doctor, culminating in the regeneration? But he stayed because he cared about those people, not because he thought they were tiny and silly. And when Lundvik asks “Who put you in charge?” in Kill the Moon, he doesn’t tell her precisely why he should be in charge, as he does (as Ten) when Rickston asks the same question in Voyage of the Damned, he just says “Okay, you say ‘run’ then!” It makes total sense that Clara should have an outburst and take the Doctor to task for leaving when she wanted his help, or at the very least his support. But this particular outburst doesn’t make sense to me.