Things going away in the x-pac

[Reynhart]

As long as phasing only prevent you to "see" other people, it's not such a big deal.
You could keep a universal chatlog to be able to hear them, you could still invite them for dungeons, etc...or they could also give them a "phase" cursor, like the CS or levequest one.

Besides, "open world" quests already use some form of phasing with quest objectives, and "instanced" quests don't require you to move to your location, so you wouldn't even have to see the world.