To be fair, Bungie had significant motivation to fix something that directly effects their bottom line, so they would likely put a lot of effort into that (they could easily justify paying overtime or bonuses if doing so makes the company far more money). With a weapon patch, they don't have as much to gain with an immediate fix. There's also the fear that messing with guns could have a negative outcome in terms of balance. Since they don't have an obvious financial reason to make a change quickly, they will naturally take their time to be sure that their fix is "the right" fix. So it's likely less about the actual coding, and more about feeling okay about taking their time testing something before rolling out any weapon changes. They are also focused on new development, but likely dropped that temporarily to fix something that hurts their pocket books. Quite frankly it's a business decision on where to allocate resources. I can't think of many businesses that wouldn't have all hands on deck to fix something that could cost the company an enormous amount of income. Or perhaps this: (Warning, do not click if you love Bungie) [spoiler]Another sketchier possibility is that the free books were planned and not a mistake at all, and they had a "update patch" premade before releasing the initial December update. They could have done this in hopes of getting some people who wouldn't have bought the book initially to buy it after getting the rewards. I hope that's not the case, but it is a possibility. It also would explain how they were able to "fix" it so rapidly. [/spoiler]