I can't speak for the GP, but I personally find editing code in my IDE to be a smoother and more productive process than editing any type of serialization or markup format like YAML (or JSON, or RON, or EDN to a bit lesser extent). This is most likely due to me being so used to being on the other side of those formats, or generating them with code in the first place, and not necessarily because one is "better." My IDE setups will reflect that preference, which in turn makes it stronger.