Fishing with dredge bars (both with soft-baits and real baits) has been popular with billfish anglers for sometime now. The whole idea is that the school of baitfish that the dredge bar simulates draws the predator in to your spread that will then take a trolled or pitch bait. 

Hogy Softbaits make deadly dredge baits. Their longitudinal flex is more typical of a swimming baitfish. NO TAILS TO VIBRATE OFF!