Reviewing ones footage are a good idea now and then, highly recommended to do.
But of course you cant view every file in its entirety as that would take as long as it took to record it, and there are many hours of footage on a 400 GB memory card.
What i do are focus on first and last file in a drive session, and then launch it to verify it can play in my player of choice, and then immediacy close it again just so i can see where first file start to record ( mostly at my home as i set off, or any of my regular destinations )
Same with last file that are normally in one of my choice destinations or my home, anything else like mid drive some distance from a known place make a bell ring with me.
And then i do the same with some random files thru-out my memory card, and to do that i use 5 - 10 minutes at the computer for a 128 GB memory card.
I find i drive the same routes again and again, so by now if something happened in so and so intersection on my route i know i will have to look at say the number 9 file in that drive session.
It would take some time to look over a 400 GB memory card my way, but it is not something you have to do more than say every month or two maybe 3, and then the time spent on the computer are way better instead of become one of the guys that say " i put a dashcam in my car 3 years ago, and now i have had a accident and find it have not recorded the past 6 months "
If a file can launch on your pc in what ever player you use, all of it should be good and viewable, so reviewing your footage you only need to watch like 5 seconds or so of the files you sample.
I think thats what is meant with reviewing the footage.
If some one mean to review their footage 1:1 thats just silly in my book, not least if nothing at all happen, and should anything happen use the manual event button.
Same with some people wanting their LCD live all the time, why the hell would you want to have the view you hopefully are looking at out the windscreen playing on a stamp sized screen too, even if it is the rear camera thats still silly as most cars have a mirror that will let you see things back there even better.