When phasing happens it can be jarring, but it’s obviously necessary. In my experience it’s not something that negatively impacts WPvP, especially since it’s occassional.
- Queue jumpers - if someone has potentially waited an hour+ for a queue, NOTHING must prevent them joining. Yes it can be abused, but regardless of opponent’s reasons - I consider it a win for me.
- Unlocked or single faction locations - phasing is a necessity here. Avoid location or accept the location’s quirks. Open to abuse, but again, if opponent phases out - a victory for me.
- Enemy group phasers - this is a necessity, players have to phase to same shard when they join a group, no way around it. Some prefer the ol’ days before LfG, but this phasing is part of what makes WPvP active in War Mode. While I love 1v1, I’m always looking for enemy groups - so when one phases in, I consider it a benefit to me.
- Faction balance - WM auto balances players in a zone, a necessity. PvP servers were notorious for unfixable imbalance, WM shards are the solution.
The above is just my opinion, but there’s more than only the negative way of looking at phasing. Overall what we end up with is a game mode that provides almost guaranteed action - random anything goes WPvP. Love it. 
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