it was just to prevent breaking of the HBD price to the high side of the peg
I am no savvy trader :) at least not in Hive ecosystem. However, I must say that HDB have been stable for a while now. Also hive is deflationary due to smooth's mechanism, which have been reflected in the price.
RE: Is The HBD Stabilizer Frontrunning Everyone Else For HIVE to HBD Conversions?