Better video quality = bigger bandwidth requirements. And then other Channel 9 users would be bitching about how long it takes to download, or how it won't stream smoothly over their connection. So it's a compromise.
Don Syme and Andrew Kennedy from MSR Cambridge came up with
the implementation techniques used for .NET generics - and they beat pretty much everything else out there in terms of expressibility, speed, and performance. Note that the original paper is from 2001: it can take a LONG time to take a good idea from research
and get it into the hands of customers!