Oh man, I tab away from this window and Edi beats me by an hour.
My system for using Acashic Record at this point (and it's not often I do) is to saturate my territory with Arcane Probe first, to get the pearls rolling in. Then once that's done, I only do AR on swamp and waste that have 0 sites so far. Seems to do fairly alright for itself, usually.