Commuting isn't a sport though. It's just transportation. To me it seems very much like strapping a camera to your head and recording everything you do all day and then storing and reviewing that every night. I could perhaps see having a 30 minute buffer thing so in the event of any sort of accident you would have the last 30 minutes of your ride, but even that seems like expecting to be hit. To me biking is no different than taking my car or the bus to get somewhere, other than the fact that I like it better. If I sprain an ankle getting off the bus, or someone dings my car, which are both far more likely than me having a bike accident if the last 40 years are anything to go by, then I wouldn't expect to have a video of that. Maybe if we, the bikers, didn't treat biking so differently from other activities, maybe others wouldn't either. Including your wife.
Its a tool my friend. For example, if you got hit and it caused brain damange and you could not remember anything. Or if you got hit and killed. Gives your loved one evidence that could help out. In my area, we have one of the highest hit and run rates in the US. I do not want to burdon myself, my wife or my family.
I get your point and respect it but when it comes to commuting, it is another tool to use.
You can use the video, also, to track patterns in driving, areas where you ride, and learn from mistakes.