Post dive report - display where I dove

This would be impossible to determine with any degree of accuracy. GPS doesn’t work underwater, and the watch/dive computer could never know if the path you took underwater was a direct line from entry and exit point or if you were going around in circles.

A couple thoughts. It’s the apnea hunt mode I amusing because I am spearfishing. So I am frequently on the surface where GPS would always pick me up    Furthermore, if I wear my Apple Watch while I hunt, it can display my entire path throughout the hours in the water.  Does the Apple Watch not use the same GPS?

GPS satellite radio waves (and generally most RF waves such as WiFi and Bluetooth) do not effectively penetrate and traverse water, and it is just impossible to obtain a GPS signal underwater using recreational GPS devices such as an Apple Watch or any Garmin GPS devices.

Whatever reading your Apple Watch is giving you is likely very inaccurate or relying on assisted GPS (using cellular triangulation to more quickly secure a GPS lock) when above water. Any underwater movement is fancy guess work and estimates built on already inaccurate GPS points. 

I'm just thinking outloud with you now: I assume Garmin could program a new profile to try to capture a GPS location point whenever possible, but this would drain battery inefficiently because it would constantly be searching for a signal underwater. Perhaps the profile could be set to try to capture a GPS location if the depth gauge is sensing you're not submerged? Again, it will likely be inaccurate and it'll never know your movements underwater.

Nevertheless, it would be a cool feature to have but the technology we have right now is limited in this regard. 

Good education, thank you very much. If I posted a dive in swim or hike mode, it would record my travels…but I’d obviously lose the valuable dive data.   What I’d love to see is where I went AND the dive data.  It just seems like if the watch can collect both those events, so it’d be awesome if it could combine them. 

I'm glad you found this info helpful. 

Also I agree but itj you, it would be an awesome setup. Maybe this is something Garmin could look into?