HOW is hill strength calculated?

I had my stryd attached to my shoe, but I'd gone to settings and turned off that connection.

I then had the wrist power enabled.

When I ran I found power numbers appering in the stryd data field. Sure enough when back home and staring at the data I found the watch had indeed connected to the shoe even though I had explicitly told it not to connect.

If you mean you turned off the Stryd power meter connection in the watch's built-in sensor settings, it doesn't matter.

Stryd Zones does not use a connection controlled via Garmin's built-in/native sensor settings/menu to communicate with the Stryd sensor. This is the flip side of what I tried to explain above, where Garmin's native power features do not ever use 3rd-party sensors.

Stryd Zones directly communicates with the Stryd sensor using ANT+, via the Connect IQ API, regardless of whether or not Stryd is natively paired as a power sensor or a footpod. Stryd supports multiple simultaneous channels of communication, which is why Stryd Zones still works even with Stryd is natively paired.

None of this stuff is a bug, it's all by design. The main reason is that there's no ANT+ running power standard, so Garmin doesn't even have a concept of natively pairing running power meters via ANT+ - that's why Stryd Zones is required in the first place. As I said above, when you pair Stryd as a "power meter" in the built-in Garmin sensor menu, it's being paired as a cycling power meter. You'll notice that Stryd Zones collects lots of other information besides power - none of those metrics are defined in the cycling power standard (obviously), since they're related to running power.

What you should find is that the built-in power from wrist numbers should be different from the numbers displayed by the Stryd Zones field. But ofc that's a given.

If you mean that you changed the ANT+ ID to 0 in the Stryd Zones app settings, it also don't matter. In that case, Stryd Zones will automatically search for a nearby Stryd and pair with it. Stryd support does recommend entering the actual ANT+ ID so you don't accidentally connect to someone else's Stryd.

If you don't want Stryd Zones to connect to your Stryd, you would either have to put a fake ANT+ ID in the settings, or remove the data field from your activity.

Do you have also the Auto-Detection option disabled, in Sensors & Accessories?

It doesn't matter, for the reason I said above.

What people need to understand is that as far Garmin's built-in features go - like running power and sensors - Stryd running power may as well not even exist.

Stryd presents itself as a cycling power meter and a footpod, as far as the standard Garmin stuff goes. The Stryd running power stuff is proprietary, does not and cannot interoperate with Garmin running power, and requires Stryd Zones to work properly. The Stryd mobile app requires all the additional metrics that Stryd Zones collects. This means that 3rd party CIQ apps (not from Stryd) can't just pair with Stryd as a cycling power meter and write the power data to the FIT file, because the Stryd app will ignore any data that wasn't written with Stryd Zones.

Yes, in the past there was a loophole where 3rd party CIQ data fields could display the running power value that Stryd also transmits over the cycling power channel, but that loophole has now been closed in the latest beta firmware for Fenix 7. I assume it will eventually be closed for other devices as well.

Besides, that loophole was mostly cosmetic, since built-in Garmin running power does not use data from 3rd party sensors, including Stryd paired as a cycling power meter.

Fair.

I just remembered that in their support articles  even Stryd recommended to pair the pod as an ANT+ power sensor saying that one should refrain the pairing of it as a BT power sensor / or pair the latter, but disable it.

What is the point behind qm

Why is it not enough /for Stryd support/ to pair the pod only as an ANT+ footpod to a Garmin watch qm

What is the point behind

- There's no ANT+ running power standard, as mentioned above. Different vendors (such as Garmin, Stryd, Polar, Apple, and Coros) may not even agree on the definition of running power itself

- Stryd can transmit running power when paired as a cycling power meter, but not all Garmin devices natively support cycling power meters

- Even though Stryd can transmit running power via the cycling power protocol, it's not enough because the Stryd app uses other metrics such as form power and leg spring stiffness. (Besides, a Garmin running activity won't record cycling power, so there needs to be a 3rd-party app in any case.)

- Therefore, Stryd has its own proprietary protocol for running power which requires its own CIQ app (both to collect the data and to record it.)

It's just like any other proprietary / non-standard sensor that requires its own app (like the Moxy muscle oxygen sensor).

Why is it not enough /for Stryd support/ to pair the pod only as an ANT+ footpod to a Garmin watch qm

Because ANT+ footpods can't transmit Stryd-specific metrics like running power, form power, and leg spring stiffness.

The footpod functionality is just there for people who want cadence (and optionally pace/distance) from their Stryd. It's added value functionality, but it's not the main functionality of Stryd (running power).

> even Stryd recommended to pair the pod as an ANT+ power sensor 

If Stryd support is recommending pairing the pod as an ANT+ (cycling) power sensor, maybe it's so 3rd party non-Stryd CIQ fields can also access Stryd power in run mode (via the Connect IQ API - activityInfo.currentPower) [*]. Could be that they're trying to avoid support questions like "why isn't Datarun Ultimate working with Stryd???"

Since Stryd Zones makes a direct ANT+ connection to the pod, it makes no difference to Stryd Zones whether the pod is paired as a power sensor or not.

[*] As discussed elsewhere, the latest Fenix 7 beta software has closed this loophole