Having a running video log robs the officer of of his most valuable asset, which is his discretion.
Hey, Joe, how ya doin? You treating my sister right? Well, you can just go on your way. If I had known it was you I wouldn't have pulled you over at all.
I will agree the concept does cut both ways
I think the real reason why cops should be begging to have their actions videoed is because there are so many cameras out there and editing is so easy that they better have their unedited version available to counter it if they didn't do anything wrong. Otherwise it will be their word against a Youtube video with a million hits and they will lose.
What's going to happen when an LA cop gets into a questionable action and when asked for their video every cop there claims to have had an unfortunate equipment failure? Their claims of innocence will be met with the same contempt that Lois Lerner's are.
The days where they could grab every camera and destroy the recording to keep their actions from being seen are long gone. They will be recorded and there is nothing they can do to prevent that.