Awesome. I'll look up TSS and do some reading about it. On my rides so far the zero times are restful by definition, though they are only occurring because I've come up to an intersection, and I don't believe my output would have dropped had the intersection not been there. I do appreciate your tips and advice here, and I'm looking these things up, then looking at my data as it comes in to try to see what they're about and how to use them. I recognize that I'm approaching this from a position of ignorant and assumptions made prior to having power, and prior to having read up on the stats collected or calculated using power data, so I'm flexible in my opinions and approach.
I discovered that the left and right halves of my Stages LR power meter were not in fact linked together from the factory as they should have been. This means the power data from my first four or five rides with it were using left-only power, which was then doubled. I linked the two halves using the Stages app on my phone, re-paired the power meter with my Edge 530 and Fenix 5 and now not only am I getting proper dual-sided data, but on my new Garmin 530 am all of a sudden getting all this interesting L/R split data. It revealed immediately that I've been pushing harder with my left leg to varying degrees (that changes with increasing cadence), so now I'm watching for that and trying to pedal more evenly with both legs.
I was able to cut the zip-ties and remove the Garmin cadence transmitter from my chainstay and pull the rare earth magnet from the pedal stud on my left crank, since the Stages power meter sends internally generated cadence data. That's one less accessory strapped to my bike.
I've seen what I needed to see by recording rides both on the Fenix 5 watch and on the bike computers, and now that I'm confident that everything's set up and working properly on the Edge 530, I'll stop also recording the rides on the watch. As for how I'm feeling about my virus-anxiety-driven comfort purchases, I'll say I'm delighted with both the Stages gen 3 L/R power meter and the Garmin Edge 530. I've got way more info about my rides to geek out over, help me out in planning my rides, and the 530 has new connectivity and features that I've really loved on the Fenix 5 watch, and is a real step up from my trusty and faithful Edge 500.