Yes, it is clear that the HBD stabilizer makes more profit when HBD fluctuates a lot. @dalz has produced a number of reports and charts showing big profit gains during previous volatility episodes.

Mechanically, the way this profit is realized is by the stabilizer pulling extra HIVE (that is, HIVE with value in excess of the amount of HBD funding provided to the stabilizer) out of circulation and sending it back to the DHF, and also in the form of HIVE fee burns performed by the blockchain when HIVE is converted to HBD (which the stabilizer does a lot when HBD is overvalued)

cc: @johnhtims