It would be useful if there were an identifier to return the address specified in a /server command in order to identify a server connection when $network and $server can't be used. Twitch.tv provides a perfect example because it doesn't send the $network name and the $server name has been unreliable in the past.

If you add the twitch servers to your server list under a group you're able to use $network as early as the logon event.

When is $server unreliable? Before the server overrides that identifier it will return the name you specified in /server.

Twitch has broken scripts relying on $server in the past (tmi.twitch.tv became testserver.local on some of the servers for a few weeks).

I wasn't aware that $server used the value from /server before the servername was sent (I never thought to check the on logon event). That should be reliable alternative, and wouldn't be a big pain to keep track of.

I still think it's a good idea, I've seen people asking for this in the past on IRC because of their bouncer, basically they were saying there is no way to know that your connection is connected to a bouncer in a reliable way without scripting.
Having an identifier which returns what was used in /server would actually help people in at least those situations