I only use single hook setups #4 or #6 but if you think about it, steelies are smart fish and will spit your bait out before you even know you had a bite. So a double hook setup would just put more hooks in their with the hope that one out of the two sticky gammies will find its way without you feeling it. Or when using eggs, the first hook gets covered up normaly by roe so the second can be exposed. I'm not a pro guide but thats my 2 cents.