: Without the use of the Halo Array, if the Covenant had to defeat Earth and
: her colonies inch by inch, from one world to the next, I'm sure we'd get
: very brazen with our disruption. Red Flags would be thrown everywhere and
: the galaxy would bathe in Novas.

I think if that event horizon existed, it would have been crossed after the fall of Reach - yet there's no evidence that something like this happened during the battle of Earth.