The video output is more of an afterthought, I think. The primary purpose is to be a ODE, and they knew that they needed to have at least audio output for proper sound. While you're doing that, you already have easy access to RGB and composite, so all you have to do is add a DIN and a few caps/resistors and you have a cool extra feature.
Unfortunately, it seems that there is a design flaw and the RGB output is pretty noisy. They're working on a fix. I haven't received mine yet to see for myself.