A common irritant while driving is the jackhole who pulls right in front of you… only to immediately slow down. In the US, this is generally a problem of the jackhole in question being dimwitted or oblivious, but in Russia it seems that this may be due to the jackhole being drunk, or pulling an insurance scam. Thus dashcams prove their utility once again.
Now if you are going to pull in front of someone and slam on the brakes, you generally don’t want that someone to be driving a very large and heavy vehicle. Physics is not on your side in that case. If you are, conversely, driving a very large heavy vehicle and someone cuts you off and slows down, you may of course be tempted to slam on your brakes… or then again, maybe not. Meet Alexei Volkov:
A bunch of his vids are HERE.