If you drive as much as I do a day and see as much accidents on the road as I see, you wouldn't be asking that question. Just look at the youtube link I posted.
I drive on the freeway daily and see things like that often too but have learned to simply anticipate those situations from experience. I see those types of drivers before they opt to cut me off and assume they'll pull a move like that. Nothing really throws me off anymore but then I've been driving for 40 yrs now.
Still, so the idea is to continually run a camera just in case, to protect yourself legally in the event that the cops and/or witnesses don't get it right?
I have yet to see someone pull the reverse into your bumper gag but yeah, that could suck w/o a cam or witnesses.
I was thinking about
HarryLui's video and actually if you look at it at 1:20 you'll see, hear that he's accelerating so to me, I'd say he knew the guy wanted to merge into that lane and probably even had his turn signals on. So, in that vid, if there was an accident it's possible that the vid as evidence could backfire in the view of the law. The proper thing to do would be to just slow down and let the guy in. I deal with that exact same merging situation in rush hour, never-ending road construction traffic daily. Either I have to merge in to get over or I have to let someone else in.