> The older peers have already completed the first few files and thus aren't interested in younger peers who currently download the first file exclusively, thus no mutually beneficial relationship can be established between different "generations" of prioritizing peers, effectively splitting the swarm into sparsely connected sets.

I don't understand this. Why does it need to be mutually beneficial? The peers should "pay it forward" by uploading to younger peers, even if the ones they downloaded from are not benefitting.

> On a small swarm this behavior can lead to pieces drop to the 0 availability because some peers concentrate on the first few files while the last peer/seed that has the rare piece in one of the later file quits after doing his fair share, but he only uploaded data for the first few files because the prioritizing peers were interested in those only.

This could be mitigated by using excess bandwidth beyond that needed for streaming to download rare chunks, and ensuring that the streaming application keeps seeding for a while after the video has been watched.

> This could be mitigated by using excess bandwidth beyond that needed for streaming to download rare chunks, and ensuring that the streaming application keeps seeding for a while after the video has been watched.

That wouldn't be streaming then, would it?

Why wouldn't it be? It is still streaming and it will start playing the video soon after you hit the play button instead of downloading the entire video first. The only difference is that it will be caching the download for a certain period of time and possibly downloading rare chunks with extra bandwidth ahead of when the chunks are actually needed. The truth is though, if the torrent is not top heavy with seeders then it is no good anyway so I don't really get why people are so focused on rare chunks.

I'd say it's more of a middle ground between streaming and normal torrent behavior.