Since you asked for comments:
1.) Have you ever seen video shot with a head-mounted camera? Ugh...
2.) Based on the images, the mount would need to be on the mask all the time... or you'd need to remove/re-thread the mask strap each time. A process that ranges from simply frustrating to downright impossible depending on your mask.
3.) Have you ever seen video shot with a head-mounted camera? Ugh...
4.) Have you noticed where/how straps attach to scuba masks? Your mount will be far enough back on most masks that the camera will be located just forward of the diver's ear. Given the FOV of a GoPro whatever video is shot will prominently feature the diver's mask, nose, cheek, reg and jaw in the shot.
5.) Given how flexible a mask strap is, the tendency for a GoPro attached via such a mount to rotate/twist throughout the X, Y, and Z axes will make for a video experience that is even more un-watchable than a typical head-mounted video. (Have you ever seen a video shot with a head-mounted camera? Ugh...)
6.) The mount will place the camera directly in the path of the bubble-exhaust from a diver's reg, causing the GoPro to be buffeted by the exhaust as well as bubbles in front of the lens obscuring whatever you're shooting.
7.) In any sort of current the camera/mount will have a tendency to pull/twist the diver's mask.
Other than that... it seems like a swell idea.
:shocked2: