Simpleboost closed loop: works by taking refdc value from rpm/map table, downscales it if 8kpa over boosttarget graph and then scales refdc directly by tpsboost graph. BoostSW is for downscaling whole refdc table. Key here is directly scale boostDC according TPS values and not by the target. Boost target is there for limit boost if refDC table is badly configured and also helps to tune that table when you see that target start