content: Sounds like they're doing packet inspection to identify specific swarms by torrent id and targetting them that way, likely using some sort of automatic throttling based on arbitrary popularity values. On the up side (for them) that means they can white-list a lot of stuff to preemptively address anything like this, but on the down side they probably won't, and a lot of legitimate torrent-based distribution will get auto-throttled for days before it is manually corrected.