For what it's worth, this is fairly standard binary patching approach as used in software updates. I am aware of at least two mainstream titles that do this, an

For what it's worth, this is fairly standard binary patching approach as used in software updates. I am aware of at least two mainstream titles that do this, and I'd be surprised if Firefox, for example, doesn't push updates this way. (edit) That's an awesome name by the way. Railgun.