Need Feedback on Setting 390 with Adjustble Rockers & Hydraulic Lifters

when i rebuilt my 390 w/ Hydraulic lifters, it never had hardened valve seats installed(previous owner lied) and the heads needed so much valvework done it required Adjustable Rocker Arms. When i set the valves initially i tightened 1/2 turn past "No Spin" on the pushrods. I never had any problems, the car ran great. After researching it,and the many possible ways other people are setting valves, i thought it made more sense to use the method of 1/2 turn past "Zero Lash" instead. After setting my valves i noticed that some of the pushrods were tight, no spinning possible and some were still spinnable. I am adjusting with engine cold. Although i had no problems, adjusting via my first method, it would appear to risk too much lifter preload and maybe valves not closing for some applications, Whereas the second method could end up with noisy lifters(but much preferred over bent valves huh) i had no problems but Any FEEDBACK, Ideas, Slaps upside the head, are Greatly Appreciated. am i correct? zero lash means just to the point where up/down side/side movement or play is eliminated, right? and.. Does the Hydraulic action of the lifters under full oil pressure Extend the Lifter any? can it push the lifter open farther than the spring inside does. Or does pressurize just enough to keep the lifter on the cam lobe?