Yesterday while changing the blades on My ZD18(54") I checked the blade height and pitch. The height was off 1/2" so i made an adjustment.The pitch was close to 1/2" also...so i changed that to 1/4". Now to my questions.... Does less pitch=less airflow? I would have thought not. It seems to have a better cut but leaves more stringers( i know that sounds like a contradiction) which causes me to think... less suction Where does the deck gets most of its air?