Well, I guess having the TARDIS suddenly go thermo-nuclear in the middle of the Powell Estate,
on New Years Day 2005, as The 10th Doctor regenerates before Rose Tyler has even had the
chance to meet the 9th Doctor would definitely mess up her timeline and cause a paradox.
I can imagine the scene . . .
The 10th Doctor staggers back to the TARDIS for the final time as the regeneration begins.
The Doctor:
"I don't wanna go!"
Moments later, the Doctor's most violent and destructive regeneration ever finally kicks in,
causing the inside of the TARDIS to burst into flames, and the windows to be blown out.
Jackie:
"What the hell was that noise?!? Sounded like an explosion!"
Rose:
"Mum ... there's something on fire outside, looks like an old phonebox."
Jackie:
"Probably kids setting fireworks off inside it. Y'know what they're like round here!"
Jackie looks out of her kitchen window, and witnesses the TARDIS ablaze.
Jackie:
"It's an old Police Box! That was never there before! And it's on fire!"
Rose gets her mobile phone out of her pocket.
Jackie:
"Rose, what ya doin' ?!?"
Rose:
"Callin' the fire brigade, whaddaya think I'm doin' ?!?"
The 11th Doctor:
"GERONIMOOOOOOOOO!!!"