Piracy is an issue, because you would only need to spoof the initial b.net authentication then you could play offline with full functionality instead of having to constantly remain authenticated. It makes it a huge amount easier for pirates, so it is an issue.
Secondly having p2p hosting is a huge redesign of their architecture, it's going from a centralized system to a distributed system, I can't see how that's even open to debate respectfully. It's like a website download as opposed to bit torrent.
Blizzard have constantly said that the number 1 feature request by the community (LAN) will not be implemented.
It's currently P2Blizzard2P (one of the peers hosts, just all connections are trafficked through Blizz servers). What about allowing players to play against players on the same subnet to just skip the Blizzard part of that is a huge redesign?
It's more like going from a remote third-party hosted connection to a direct one (imagine if your p2p file sharing client - not torrents since we're dealing with single holistic source at both ends - sent all files via a gateway that the other person could then access, but then with some sort of wizardry you were able to send data directly to other devices on your network when you didn't want to have the slowness of going over the internet). I too don't see how it's open to debate, respectfully.
Since it's limited this way, and you can currently choose to play as a guest and play against people you know anyway, there is no difference to piracy - they already give this access to you for free. So long as every time you load a campaign mission after whatever cutoff it is, or click on the multiplayer tab it re-authenticates you on b.net, you aren't getting full functionality by spoofing the login once.
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