Did you use Yahoo IM, AIM, or Skype?
Yes, yes, and yes. Works fine.
Did you use any of those for Video Chat and/or to transfer files?
Skype video chat, all the time, works fine. Don't remember about file transfer.
Did you do any peer to peer filesharing?
Yeah, I got the latest Freebsd via bittorrent, and left it up overnight and observed from the stats that it served chunks of it back to other people.
Did you play any MMOs?
No, I noted the game players.
Did you run any services?
Of course not, it's consumer DSL. I run services on my server which is somewhere else and tunnel in via ssh which, of course, works fine through NAT.
When you add in the other things that break which I have outlined above, you start to approach 75%. I would argue that 75% is a significant and meaningful fraction of an ISPs customer base.
The hypthetical network that your consumers would use appears to be very different from the actual one available to consumers around here. R's, John