Twas me that posted this here originally!
Efficiency wise you'll find it's quite efficient! Pulling the whole instance with a pally/mage yes is fast but gives not as much XP. Also, on instances like Stockades where you can basically single pull the whole instance you'll realise it becomes less efficient.
You can only reset an instance a maximum of 4 times in every hour, so pulling the whole instance, killing them (in stockades at least) takes less than 15 minutes making downtime much harder waiting the extra time for the instance to reset.
The way I (and the OP) suggested means you can spend 15 minutes pulling dotting mobs and leaving the instance and then reset the instance, this means lots of XP and less downtime.
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