Max,

No, it's not confusing. I have the Chevy version of Poly-locks - with a setscrew. They turn very easily.

If I turn the nut down lightly with my fingers, I can feel when it contacts the piston in the lifter, and the pushrod has no more slack. I turn it a half-turn and lock it. The half turn is very easy, and does not feel firm at all. I can then push on the rocker with my thumb, and feel the piston in the lifter move, so I assume that the original setting (before the half turn) was at zero lash.

If I back off the rocker and let it sit for a couple of minutes, won't the lifter piston return to full extension?

I must be having a senior moment. I've only had one solid cam in my life, and have adjusted hydraulic lifters a thousand times. Maybe I'm over-analyzing.