I said that Fire Eles will seriously hurt an entire party, but they'll never finish the powerful ones off all by themselves. An Air Spiker will kill one member of the party, but the others will be intact. If a Fire Ele works with an Air Spiker, they will make short work of a given group.

The Monk-Ritualist relationship is similar: A Ritualist can keep an entire party constantly healed as far as AoE is concerned. It can't counter spikes so easily, though. For that you need a Monk that is capable of spike-healing.

I'm not saying that one is better than the other. They are just different. The reason Fire Eles don't dominate in PvP is that Monks have time to counter the area-wide health loss and intelligent groups are able to avoid the majority of the AoE by spreading out and/or simply moving away. Air Spikers are better in PvP because well-timed attacks can take a target down before the Monk has time to react.