In blue and red, you have available powerful counterspells and the most efficient removal in the game. Blue Moon is very capable of getting the late game, but then it's a question of how to close out the game.
Of course, Batterskull and potentially Vedalken Shackles can stabilize (if they stick), and also Snapcaster Mage + burn does solid work.
Still, this a a relatively precarious late-game plan when looking at the finishers in, say, UW: Gideon Jura, Elspeth, Sun's Champion, Celestial Colonnade... you get the idea.
A HUGE part of the slack is picked up by the unbanning of Ancestral Vision, which gives us the late game gas (plus it's easy for this strategy to get there w counters and burn) sorely needed.
The burn aspect of UR control permits us to take care of early threats and also lots of dangerous tech cards (e.g. Dark Confidant, Noble Hierarch, you get the gist). But burn is shaky the larger creatures that are seen late game, but luckily big creatures = attacking creatures, and Batterskull really helps break that stalemate in our favor (coupled with burn spells actually serves as very solid removal, oddly enough).
This deck is favored G1 against most decks in the format, with the clear exception of Affinity, Burn, and Merfolk... a G1 Blood Moon can really catch your opponent unprepared.
