Re-uploaded using GoPro phone app instead of laptop version. I ran the same camera data through the GoPro phone app, instead of the laptop version. And it looks like besides its algorithm filtering it gives a 1 sec average. It's saying I hit a sustained 35 point something. The speedometer moves really smooth. It's display is simpler. It just has marks, not numbers going around the speedometer. It's a good way to tell which version someone used. If you see numbers going around the speedometer be skeptical. I'm only going to use the phone app version from now on.

Date: April 10, 2022
Spot: Clinton Lake, IL
Rider: Reid Fillman
Sail: 4.2 Ezzy Tiger
Board: 95L RRD FSW
Fin: 31cm MFC Freewave
Camera: GoPro HERO6 Black

Even when the camera has established communication with whatever satellite, GoPro GPS/speed data is known for inaccuracy. Users have complained online for some time now. I'm on my 3rd GoPro and they all had accuracy inconsistency in a fairly random manner - and at times wrong by +/-1 to 2mph compared to my GPS watch.
For more accurate data, I would suggest using either a Garmin or a Locosys GPS watch or device. These watches can be expensive and I understand that they might not be on everyone's budget. But if comparing performance is the goal, one of these watches might provide a better perspective. At least it does for me.

One of the things I came across is the antenna on the GoPro is located on the top by the start / pause button. And they said the GoPro GPS should never be used when it's upside down. I also read that watches should be face up on the arm if folks sail front arm underhand or change on the run.

I also think the GoPro Quik desktop should never be used for GPS gauge overlay now that I've seen the nice filtering and smoothness of acceleration of the GoPro phone app version. I should make a side by side vid of the same run. 4 mph top speed(35 - 39) difference of the same data. With that said even with the chaotic desktop version it did hit 36 mph 4 times in the run. Still staying with the GoPro phone app 35 mph 1 sec average. Now i'm wondering if a GPS watch would have given me 36 mph MAX. It would also be nice to have the point whatever speed to see how close you come to the next mph.

Your watch looks awesome, all speed info on the face realtime. We'll have to have a watches topic thread.