From what I've seen and heard from you guys, I think I can sum up some findings:
1. The key to valve lifter tick suppression is sufficient MoDTC ("Moly") additive in the engine oil. This was proven by low Moly oils being boosted with LubeGard Moly additive, and High Moly Oils, particularly Red Line. High Zinc (ZDDP) additive oils without high Moly did not work (Travis).
2. Moly additive content is important - Burla has test data evidence that Moly concentrations up to 200 ppm reduce metal wear. My recent comparison of Red Line 0W-30 new and used oil samples showed Moly depletion of 60 ppm (12%) from 499 ppm new in ~ 3,000 miles runtime. Extrapolating out to 5,000 miles OCI, Moly depletion would be ~ 100 ppm. This means new oil Moly level of 300 ppm minimum is beneficial.
(Moly depletion is normal and expected - it means Moly is plating out on high friction metal parts)
3. Oil flow through the engine internal lubrication system is critical. Methods to maximize flow rates are important. Among them, lower viscosity oil in colder climates, increased idle speed to previously-normal 750 rpm, Melling or Hellcat Oil Pump for increased flow, lower restriction oil filters like Royal Purple or Wix XP. Fram Ultra is inbetween - more efficient than Wix, but more restrictive than Royal Purple. Any of these three will perform ok.
It may also help to pre-lube an engine that's not run in more than a day. I pre-lube by cranking several cycles without starting. This ensures oil has flowed through most of the oil circuit before start. Do this by pressing the gas pedal all the way to the floor and holding there. Step on the brake an push the start button. Remove foot from brake, then press start button again to stop cranking.
4. It is unknown if base oil formulation has substantial impacts. We've postulated polyol ester (POE) base oil blends could help because of their polar affinity for metal surfaces. But we haven't seen evidence Red Line (a POE blend base oil) works better than a conventional synthetic like PUP spiked with Moly (LubeGard).
We know Red Line works for most, as will Pup + LubeGard. Again, the key is 300 ppm minimum MoDTC (Moly) additive concentration.
Thoughts? Questions? Additions? Subtractions?