No, the problem here was maintenance was TOO up-to-date. This whole bike was just built frame-up from freshly-cleaned components. And pre-ride check wouldn't have helped either, it shifted fine when I did circles in the cul-de-sac, the problem didn't manifest for a few miles. Do you hand-tighten every bolt every time you ride a bike?

The lesson here is, when you take a first ride on a bike after working on something, you should be MORE likely to bring tools related to that something, not LESS. And in this case since I had touched EVERYTHING, it was really stupid to ride totally empty-handed.