Blackfish are aggressive feeders that can snip the bait from a hook with surprising ease. For this reason, it makes sense to present two baits when bottom strucuture isn't particularly sticky. This rig does the job especially well by placing a pair of crab baits close to the bottom where bulldogs like to hold. Use small, whole crabs for bait if bergalls and other pesty bait stealers are a problem. Use shelled, quartered or halved crabs if the tautog clearly predominate. Some bottom bouncing veterans also like to offer different crab species on each hook until determinig one is more favored than the other.