http://forum.bioware...7#entry16394239
О DLC
To integrate DLC content into main content requires the main content to be patched in order to support that content. The more the content is integrated, the more patching is necessary. This creates a risk because every time you change something, there are potential knock on effects that might not be properly known. This will affect people that have no interest in the DLC, since the patch must be deployed to the main game and cannot be something that is only applied to people that own DLC. This goes beyond simply "it's a nightmare to try to support multiple versions in the wild," but is also the type of thing that First Party certification isn't very keen on us even allowing (for many of the same reasons).
Internally, development is not as seamless as if it exists from the start, because you have to keep the packaging separate otherwise we'll make things even more complicated during development. If we don't keep a distinct "patched version of the game" and "DLC focused content" and just start adding that new content and merging it in with the main game's content going forward, it means we'll need to spend a fair amount of time trying to decouple "patch content" from "DLC content." I cannot overstate that his is NOT a pleasant task for whichever poor source control expert gets saddled with it. We actually had something similar happen to one of the builds on DA2, where it wasn't properly archived. Patch content kept happening on that content, but once we realized the archive was missing a programmer literally spent days ensuring thatnot a single thing that existed in the release build was missing, and that not a single thing that existed after the release build was present, because it'd cause serious issues as we'd be attempting to build a patch on a build that didn't actually exist in the real world.
Depending on how we do our bundling, this can really explode patch size requirements if lots of different aspects of the game end up getting touched that otherwise wouldn't be.
