@David - we give Stress Points, which is functionally the same as TSS. TrainingPeaks has basically “open sourced” all of these metrics - you no longer need to license them - as they have basically become public concepts. Plus, they are pretty simple mathematically. FirstBeat, on the other hand, has not actually ever published (that I know of) how to derive their training load values, which are based largely around heart rate values (and variance, I think) within the workout and how it correlates to speed (running) or power (cycling).
We don’t show kJ on the ride summary, but we easily could. It’s just not clear that there was (or is) a real desire for it. Most of the people who care about kJ are viewing the FIT files in TP/WKO/etc
As far as calories, that’s also not proprietary. FirstBeat may have their own proprietary calculation that factors in HR, but we simply use the commonly accepted metric of human cycling efficiency of approx. 25%, so kcal = 0.25*kJ. We are simply showing calories (rather than kJ) because we figure(d) that was/is more relevant to most of our users.
But any of the training load metrics that are power derived - ATL/CTL - can be done from our fit files by any of the software programs that do it. If you use Strava - which requires a HRM - they again are pulling that from the FIT file - which has a standard format which we follow.