Cover is a good PvP skill. It's super niche in PvE, but has it's place. If you don't feel like flash spamming to slow your DPS down in a speed run, you can just cover whoever is spamming the AoE.

However, in 8-man it get can get really hard to target the right person, especially in the heat of the moment. I used cover a lot when bee's would spawn in AK because they usually went right for healer. OMG remember when tome dungeons were somewhat difficult.....I just made myself so sad.