Nice! Thanks for the info @gpagnozzi, really appreciate confirmation that [z_tilt] is expected to work.
Your post helped me take another look at my setup and wiring again… Turns out I’d messed up the wiring and plugged one of the steppers into motor2_2 
, instead of skipping, similar to what we do for SKR1.2 Pro.
Fixed and finally have z_tilt working now 
Here’s the stepper wiring that’s working for me…
Seems to take z-tilt 6 attempts to satisfy the retry_tolerance: 0.005 value. Am double checking distances/dimensions of my pivot points to see if that helps. Also moving probe positions as close as possible to pivot points should help.
Even so, I (a Klipper Noob) don’t understand why 0.005 tolerance is needed given the 0.645mm variance observed for my Alu plate. Measured at room temp, no PEI/magnetic layer yet, bought from amzn. Probably not Cast Alu, which I learned would have been more stable during hot-cold cycles. I may also have warped the plate further when cutting down to size with angle grinder. Am still learning what mesh variance most people find acceptable?
Looking at ways to speed up since z-tilt is needed before each print. e.g. Sleep intervals between probe readings seem unnecessarily long (~1s), looking into that too…
Am loosening retry_tolerance: to 0.04 for now until I learn better, and/or someone informs me? Tolerance of 0.04 is helping z-tilt process complete faster with just ~2 attempts.
Cheers!