Sorry, this was supposed to be a thanks but I got lost in the details. So..thanks for all the replies! I singled out K.I.S.S because he/she pointed out the separate issues of stiction/friction vs viscous drag. Once I realized I was not addressing each one individually I changed the design to do so. I can't machine the tolerances I need so I used a small HDPE shim-ring to gap the two sliding surfaces, and filled the remaining un-filled gap with stiff grease. Viscous drag now stays constant because grease isn't squeezed out, and friction is provided separately by the shim size and material. I think what I was calling 'stiction' was not the usual hysteresis between static and kinetic friction (because that should be evident immediately), but the transition from a friction-based resistance to a viscous-based resistance when I first attempt to turn it for the first time, which is huge once the grease has been statically compressed for a day or so (not sure exactly what was going on; some kind of vacuum-weld effect?). I'm still using a compressed spring to clamp it together. The sliding surface of the shim is highly compressed with the spring so it (should) stay grease-free and does not enter viscous-drag behavior. The impact of the actual 'stiction' of the plastic shim-ring is minimal because I didn't need a lot of friction anyway (and I'm using a slick plastic). At this point I am just dialing in the parameters, but overall it did not change 'feel' between the initial build and after sitting for about 10 days. I have to do more builds for repeat-ability but this feels like a more proper design approach. Thanks again!