Me and a colleague wondered about this and we came up with something like 3.5Mb for HD but didn't put any overhead on, or audio. Nice to see it measured in a proper way.
It was more than likely my server, rather than me.
Great measurement of bandwidth, not true picture though. Whilst it measures stream on sly sports HD.
Try running test on 60fps at 1280p on CMBC
(It wont be average of 5mbps)
Your reading 25fps at 720p thats why its 5mbps average.