it's not peer id

something to do with the way BT peer-to-peer packets are handled and constructed.

and it won't be long before Cisco catches up with this. It is a cat and mouse game.

It's common to get very low speeds on public trackers, so don't think just because you have 300 seeds your d/l speed will be fast.

TM has caught up with the 1.8x versions!

I can confirm this after 2 days & nights of experiments.
I tested on a mixture of private trackers and popular Linux torrents.

Direct -> throttled at 20-30 KB/s (no matter what time of day)
After using socks5 proxy -> 100-150 KB/s