It does strike us as a little odd that humanity's cybernetic knight-errant can just plug his double secret electronic woman into every starving alien hole. It works every time, and when it doesn't work it's because only because you haven't run from hell to breakfast trying to get this mission's alien hoobajoo. I've worked IT, enough to know that standards are porous things. There's usually a site or two out there that always seems to have last year's shit. It seems like Chief would get eventually someplace where he's trying to feed the chip into some polymorphic alloy which can't decide if it wants to be useful console or a rhinoceros, just sort of tapping Cortana on the steel horn or whatever, wondering where it all went wrong.
Of course, on one axis, she fits because she has to fit. In narrative terms Deus Ex Machina is the inexplicable "God in the Machine," except that in Halo 4 and every other Halo game that's not a figure of speech. Your body is a machine, and there's a god you kind of "wear" in it, anytime you aren't trying to stuff the god into some other machine.
The sad thing? The saddest thing, perhaps? I could actually explain why it does fit, why he can put her into all this shit. They put these answers in my head, taking up space that would other be used for sober, productive assessment of the self. I could do it with two words, but it's reasonable to expect that unless you are completely fucking nuts you haven't played through the campaign. And it's actually worth taking the time to do that, so I'm not going to put keywords in the post that won't let your mind rest - particularly if you are enthusiastic enough about the setting to have explored the corollary fiction. They made a real effort to reward the enthusiast this time around; I couldn't rob you of that, even if it means not being able to say cool words.
IT'S HARD THOUGH