I am a [b]software engineer[/b] ([i]programmer[/i] will do) and I will tell you straight-up the word "coder" is an insult. Fixing the book is actually more difficult than balancing weapons. To fix the book you have to add a check to the book (a bool) to see if the player bought it. That's simple enough but you also have to add that same check to the actual player's account. That's the bit that gets complicated. You can't just throw in "HasBoughtSRLBookOne=1" when someone ponies up the micro-transaction. You have to add the functionality to buy the book, store the purchase on the account, put in redundancies in case of power/communications loss (but that has to be stored in an encrypted file with a redundant hash so someone couldn't just sign off line, add that bit of code, and sign on). You also have to define the various variables. All in all, given the state of the code (Bungie admits it's sloppy) you are looking at a lot of bugs. To balance weapons it depends on how far ahead Bungie thought. If they were smart all the weapon stats are in an XML document and they just have to modify those and rebuild. If they were idiots they'd have to find the instances where the values are defined, modify, and rebuild. Weapon balancing software side is easy; adding a whole new feature like this book is not.