by not to heavily contended you mean congested?
if so, yeah, that is is the crux of it. if 720p is the best you can do then the internet will not provide competition to pay tv as it is starting to in europe , either.
The games I've watched have been watchable from NT. Not like the Indigenous All-Stars game we played or those NAB games we tried to film.
i've only tried to watch a couple of districts games i couldnt be bothered getting down to and they were choppy, but not as bad as the games you mention. I'm pretty sure that the ABC film the games and stream them live back to the station, where they have a half decent internet connection to upload to the servers.
Those games you mention would have been uploaded directly from the ground and i think in one case it was said over a 3g upload, so you will always struggle to get decent streaming due to slow upload speeds.