It's not quite that simple. We (I work with the Chrome team) have an RTP-based data channel (sort of what you call "tunnel through the video" already in Chrome), but it provides no congestion control or reliability. To provide those, the IETF has proposed as the standard to use SCTP. Firefox has already integrated SCTP into their implementation, and we're working to get it into Chrome. So, you can start using the API now, but it'll get much better soon.