About Time‘s central romance doesn’t involve Rachel “Mean Girls” McAdams or Domhnall “Son of Brendan” Gleeson; the real lovers here are Richard Curtis and the tricky notion of time travel. How else to punch up a story that’s all about the rich existential rewards we reap from living a boring, ordinary life? Curtis employed the deceptive pleasures of coincidence to achieve the same effect in 2003’s Love Actually, though admittedly there’s nothing humdrum about the personal relationships of Prime Ministers and rock gods (or divine intervention, even if that never made the final cut). Here, he overturns a similar stone by using a far more incredible narrative tool for his…