Even with an understanding of the universe, Halo 4's plot was contrived. The relationship between Chief and Cortana was its sole saving grace. The Didact was an out-of-character dunderhead cut from the same cloth as Bond villains. The overall nature of the plot hinged very much upon the only-recently released Silentium novel, which by all the accounts I've heard is an overwrought, convoluted, mess that tries too hard to fit Halo 4's plot into its own narrative (considering the novel was delayed for a rewrite, Bear and 343 probably decided to shoehorn various Halo 4 plot points in with little consideration for what was already written).
Halo 4's plot is not good. It's silly, convoluted, lacking in any meaningful context, and is predicated on just as crappy ancillary material just to limp along. Halos of past may not have had sterling writing, but at least they could stand on their own without having to know every little detail about what was going on (though Halo has always been notably bad about exposition).
