Tried this out last night just for fun, and surprisingly it works very well through SM armory. It's only slightly slower than warlock SoC boosting (and only due to the downtime to drink between pulls).

Posting this here in case anyone is interested. If all you have is a priest you can make it work

4 pulls in about 10 minutes

- Gear doesn't make any difference. You easily hit the AOE cap in every pull, so you might as well have 0 spell damage. Really all you need is mana.
- Pop power word shield, pull far groups with rank 1 pain
- Corutyard pull requires no cooldowns
- For second two pulls - power infusion on the first, shadowfiend + inner focus on the second. You'll get aoe capped bad on those big ones so you'll need more casts to finish them off
- Last pull needs no cooldowns - you should only have about 2 halls and you will still be hitting pretty hard with that few mobs

Not sure if it can be done in less pulls. Main problems on the big ones are your holy nova's are only hitting for about 300 and you go oom or die because nothing is dying. Might be possible to down rank to get a few more casts in.