i dont run less ign timing, i run zero. so that whole top row under SETTING, IGN MAP is all 0's
i did it for a bit of fun. that row is only touched on gearchange or when you back off on the throttle.
ie at normal idle you are on P02 as there is airflow load. when you dump throttle or gearchange airflow drops to 0 or near zero so it hits row P01.
running 0 deg IGN timing makes the car pop, fart, backfire, crack so its just a bit of fun. i love it. everyone comments on how much my car pops, farts and backfires when driving around. i dont believe there is any other gain than noise to be honest