I started fishing doubles but after so long with all those tangles I found that if the fish are biting then singles would produce about as many fish as doubles....as many fish as I wanna catch anyways. Setups and boats vary but for people like me there's just not enough room to have 4 feet between rods so Ive learned that singles with a splitshot (to get deeper) works best for me. So......that's why I fish singles vrs doubles.