HealthKit double-counting activity calories between Apple Watch and 3P apps?

How do I keep Apple Watch from redundantly mis-counting exercises that are also tracked by 3P apps?

I use Apple Watch to track my “Move” calories every day. It’s also great for tracking other daily metrics like stand time, mobility, oxygen saturation, pulse, etc. It’s great for all those things. It’s also great for tracking SOME types of workouts; yay!

But there are other types of workouts for which Apple Watch simply doesn’t have the right information to track accurately. For example going for a ride on an e-bike. Apple Watch can *guess* how hard you are working (presumably based on pulse), but the bike (at least some brands of bike) *knows* the actual pedal power (because it can measure it directly) and can integrate this power over time to compute accurate active calories. I find Apple Watch often gets it wrong by a fairly large margin (up to 30% over counting).

In my bike’s case (Bosch), there is even an app that can write workout total data to Apple HealthKit (nice) or you can export a TCX file and then use an app like HealthFit to upload the TCX to HealthKit as a workout (much nicer because it includes things like power time series, etc.) But I find that doing this results in wrong, often overcounted calorie totals (at least, as seen in my Move ring or in the workout calorie totals exposed to 3P diet apps like MyNetDiary). My question is: how can I continue to use Apple Watch to monitor basic health data during an exercise without having it double-count calories that are also being tracked by a 3P app that will later write to HealthKit? (I don’t want to take off my watch while exercising… I like having notifications/time, I like getting credit towards stand hours, I like having accurate step totals and totals for time spent in different pulse rate zones, etc. But I also want my total daily calorie count to be accurate too.)

Let’s take an e-bike ride as an example. Here are a few things I’ve tried:

1. Only use Apple Watch and ignore the 3P app. So start an “outdoor cycle” workout on the Apple Watch, go for a ride on an e-bike, then end the workout. In this case I find that Apple’s active calories total often significantly overstates the true value measured by the bike’s power meter. So wrong calorie totals are recorded in apple Health. Fail.
2. Use both in parallel. So do #1, but also track the calories in the e-bike app. Then upload the TCX from the e-bike into HealthKit. This results in 2 workouts being listed in my daily workout history (even though the times are totally overlapping) and my “move ring” appears to be credited with roughly double the real calorie expenditure. Big fail.
3. Use both in parallel then delete Apple’s workout. Do #2 but then go into apple health and delete the workout generated by the Apple Watch — keeping the workout generated by the 3P app. While this corrects the duplicated workout in my history, my total “move” calories for the day don’t seem to go back down to normal. Fail.
4. Don’t tell Apple Watch that I’m exercising. Get on the bike but do not start a workout on Apple Watch. Repeatedly ignore Apple Watch’s helpful reminder asking if I want to start a bike workout. When finished, upload the TCX from the e-bike into HealthKit. Result: the workout history in HealthKit is accurate (yay), but I *think* the calories are overstated. (It’s really hard to do a controlled experiment on this!) But I *think* Apple Watch is still crediting me with active calories during that time (since my heart rate is up) just not calling it a workout. So it seems like the result is just like #3…

I would think the *right* way to handle this *should* be that apple health should be smart enough to not double-count time-overlapping workouts. But it doesn’t seem to do this.

(I’m not 100% clear on the underlying relationship between “workouts” and calories. For example, if I go for a 2 hour bike ride, does my HealthKit daily calorie record include nothing for those 2 hours then a “lump sum” calorie entry from the Workout app at the end, or does it “trickle” in calorie expenditures every few minutes into the calorie history and then there’s a separate list of “workouts” that conveniently notes the total Calories burned in each workout — but that number is not actually read by, e.g., my Move ring? If this is the case, what happens when HealthFit uploads a TCX file? And which value is exposed to 3rd party diet apps that credit active calories against food consumed — like MyNetDiary?)

Alternatively, is there any way to just manually add negative “Move” calories to Apple Health? Then I could just do #1 but after I finish manually compare Apple’s “guess” at my calories with the true measured value from the bike and just add a negative amount to my Apple Health to offset the overly-optimistic Apple Watch?

Thanks for any advice!