I'll give you an example from personal experience. Back in 2008 I had a rclb lb7, 40 overs, single 4202, robs tuning. Truck went consistent 11.80-11.85. I thought the same thing and added dual fuelers, same tuning. Truck went 11.78 best pass next time out. Only reason it picked up anything was on the single stock cp3 it was calling for 24k and was dropping to 22k, dual fuelers kept rail at 24k. I could of added some pulsewidth and picked up a lot more but I never did, granted this was back in the early days of efi when 40 overs were huge and anything over 500hp on a SBE and you got down and said a couple hail Marys before making a pass.