Raffi Krikorian is a graduate student at the MIT Media Lab. When he heard Jack Valenti's claim that a 12-year old could share video over the internet, he decided to test out the truth of his claim. After saturating his broadband connection with a 43GB video file, he concluded:
I cannot conceive of a way to ship the entire HDTV captured MPEG-2 recording between any two residential broadband customers in the existing Internet infrastructure; no matter how "fat" the upstream or downstream pipe is in a current apartment or house, transferring the sheer number of bits that comprise a single television show that was broadcast over the air encoded in ATSC is just not feasible.
Take that, broadcast flag!
Krikorian's full report (in the form of a comment to the FCC) is here.