This videos demonstrates what I think would be possible with replay in BeamNG During the crash replay you can open the parts edit (Ctrl + W) and watch individuals parts during the crash (1:10) now that's cool!
This website is looking a little BeamNG'ish if I must say so myself http://www.eng.fea.ru/research/projects/project-19.html I wonder if BeamNG could eventually be used for real crash reconstruction, forensic crashes.
Likely what your seeing is a rendered image. Honestly your getting a lot of that in beamng. If you study the cars more after you wreck then you'll come to find out it's damn near realistic. The only problem is, the devs arent going to put the resources into this game to produce a 3d model that accurate. All of the cars you see made by Gabe are of their own design. Real world car manufactures have massive teams working together with decades of experience in the world of producing a vehicle from scratch. The time it would take to make a vehicle at the full blown realistic caliber could be used to make 4-5 beamng quality (which aint that bad) cars. Not to mention you wont have to contact NASA for a computer to handle it. Honestly the BeamNG engine could probably do what you see in that video. But it would require loads of node and beam networks to achieve very little differences. And like i said.. NASA.. The way the panels warp and smash is another story. From my observation BeamNG uses the 3d mesh and theres science under the hood to orchestrate the movement of the polys. While this is possible probably it comes down to the fact that simulating a real piece of metal smashing up with a 3d mesh isn't easy.
Thats what i was leaning towards, Its sort of how blender calculates cloth falling over a table or something, its rendered and it can take up to 2-4 minutes even using medium polys. A replay system in BeamNG would be worth hours of gameplay by itself, the best car game replay systems I've witness have to be "Driver 1 you are the wheelman" and "Grand Theft Auto 4", and now "Next Car Game" isn't too far behind, hopefully BeamNG can get something similar with the added feature of funneling through the parts manager during playback
To be honest, the first thing that popped into my head when I saw this was the slow-mo-action camera in Burnout Paradise when you smashed into a wall... that mixed in with making the body mesh somewhat opaque would make for some really sweet gameplay in my opinion! XD
I definitely think BNG will arrive at something like this down the road. Removing parts to see how the underlying parts react to each other is a huge part of the fun factor.