chrestomanci
I don't think so. If you mount an action cam on the handlebars and ride over anything other than super smooth tarmac, you tend to get a very jerky video that makes the viewer seasick …
I use a cheapish apeman action cam at 720p60 with image stabilisation on as a pedal cam. Even on off-road rides its a pretty steady image, and for the daily commute - when, as philedidiot says, people try to kill me - it's great. So I don't think camera shake would be too much of an issue.
Main problems will be losing your entire kaboodle if it falls off, and that you'd want very different angles for videoing with your phone (upright) and satnav/route tracking with your phone (no more than 15 - 20 degrees, ime). Maybe it's for when you go out with your mates and want to video them doing stuff, rather than the stuff you're doing - but then I'm not convinced that's action cam territory either… :confused: