First REAL ride update:
Went on the annual "Worst Day of the Year" ride in Ann Arbor MI this weekend. Forecast initially started out as 35 degrees F and sunny, but as the date grew closer, started falling. Morning started out at 27 degrees, and by the time we went off at 1:00 was 23 degrees with a 15mph wind. Lots of compliments on the bike from friends, including a guy I work with who kills the hills on a 196x Schwinn with 2-speed kick transmission.
Zero issues with the drivetrain this time around, and zero issues with the seatpost, and amounted to a very good ride (all roads, except for a small section that was frozen - Small Block 8's were surprisingly good, almost acting like studded tires).
One thing that I thought of, with regards to the seatpost, was torque falloff. I did the poly-spray Thursday night, carbon grip and reassembled Friday. When I tightened the clamp post down, I got it pretty d**n tight. On Sunday, before loading it up, I did one last check and it felt looser than how I'd left it. Tightened it up again and rode with no issues. Wondering if it may be the clamp or the fastener or both. Will check it out tonight, and try and figure out if I can get a torque wrench on it.