> A million copies of a 10MB PDF is 10 terabytes. A gigabit internet connection could serve that in 22 hours. Pretty straightforward to do that.

Yes, just so. The parent seemed to be arguing that it was too much to claim that it would take a few hours. I'd definitely call 22 hours at least a few!

If you go the sponsored route and use a CDN, then at 10 TBit/second it would only take 18 hours to serve it 8 billion times (approx once for every human). But there's still bittorrent and if the file's popular, that gigabit upload won't be the limiting factor.