I've trolled Ky Lake in the summer for sauger from our pontoon boat and a buddy's ski boat....the trick was to make sure we had bottom contact. The spots we trolled were on flats and drops right next to the secondary channel. Usually anywhere the water went from 20-25 ft up to 10 ft we caught fish - not just sauger but crappie and bass! Our crankbaits usually run in the 10 ft depth and we always trolled at the slowest speed possible. Typically from sunrise until 8 a.m. was the best.