Several people have posted about how enjoyable they find jumping in/through fog. If an inexpensive gadget allows it to be done more safely, then why not? After all, many, if not most, mornings with ideal wind conditions for BASE happen to be foggy. It is almost unavoidable.

Again, the device would beep once per second during the freefall, so the user would have ongoing confirmation that it is indeed working, and the user can count along so as to anticipate deployment time. Or it could have a warning tone a couple seconds prior to the deployment tone so you could take a second to react-reach-and pull.