I used to move larger equipment, D8K's 980 wheel loaders, 627 scrapers, 235 excavators, 12G grader, and many others. The thing that always stood out to me was that you wanted to prevent movement, allowing the load to gain momentum independent of the trailer. I would always check the mirrors for slack with wheeled equipment, tires squash, bounce, things loosen up. Its been well over 20 years now, since I've done that, I never had to deal with any problems with how I secured the load, was always heavy chains, and ratchet binders, as many as made sense. I don't know how many it would take to keep a D8K from breaking free, but as I understood it, the object was to make the load and the trailer as one, given the nature of things in motion tend to stay in motion. We never had any instruction on it, we used what was provided, and owners of this expensive equipment usually did not skimp on chains and binders. I never had any kind of incident when I drove, which was here locally and all over NJ, including Newark, NJ, Jersey City too. I'm aware there are regulations, though I am not familiar with them now, even then nothing rings a bell as being official, specified or similar, there had to be regulations, but like I said, we used what was provided, often times a driver who complained about improper things like this was fired or laid off. Some of this, with an abrupt stop, hard to figure how it would stay with the trailer, given the weight of these things, on steel, in principle it should never gain any momentum from loose tie downs, because they are all taut, no inertia started, in reality, and I'm no physics or engineering expert, I can't say I would trust any chain or chains in any kind of accident, you just hope it stays put, cause its headed your way, thankfully these drop decks/lowboys have a gooseneck LOL ! Straight up flatbed, its scary thought having any load break free.