I liked that the point wasn't anything to do with 'how' time travel was possible (just like those two films and to an extent ST09 where there's no attempt to make it plausible as such) - it just exists in the world of the film and it's a device used to drive the actual story and characters. That's what TT should be as much as possible.
'If the Apocalypse starts, beep me!' - Buffy Summers
'The sky's the limit.....' Jean-Luc Picard, 'All Good Things'
courtesy of Saquist