Thats odd, as MSD are doing my car and advise a recirc valve... , it is an interesting question, but sailor bob is correct about the air going "missing" once it has gone through the MAF, if it gets dumped to atmosphere, as the fuel as already been added by the ECU. I can't see how a re-flash would help as it is still dumping calculated air..., perhaps your dump valve dosn't let much air out?