how come no crys about the laynard being worn!

It stopped...didn't it.

2" straps are 10K/lb test each. And, you're not lifting the boat, you're holding a trailer to the bottom of it.

A good amount of downward tug with 2 straps up front and one on each rear corner bcreates alot of bunk friction that holds it from sliding as well.

Ditto Chris. As long as the boat and trailer are moving together, the boat will not have the momentum to snap the straps.

Well maybe they didn't want to scratch the paint on the huge f-ing D-rings...

Wrong.

I had 2" yellow industrial straps on the stern and steel turn buckle on the eye hook, plus the winch cable. When 8000 (sometimes more) pounds want to go one way and the trailer goes somewhere else... it's gonna go, and did. My straps broke, turn buckle broke.. winch cable snaped and the boat went off the trailer. Beside the fact that everythng flipped.
Tie downs is a must.. but shlt does happen. Hard to overcome physics. I'm gald they'r ok, and glad and thankfull we walked away.

When I rolled my TG over the embankment, the 4 10K straps held on. Didn't help much- everything was destroyed, but the trailer stayed firmly stuck to the boat.

In your case I can see it happening. Things get whip'n around in opposite directions, something is gonna give. For the trailer to break and slide along, the whole thing could have stayed together if it were strapped and the weight was distributed on the trailer the way it should've been. Now one scenario I haven't seen anybody come up with yet is, did hard braking shift the boat forward on the trailer due to lack of straps and break the hitch from the excess weight and the rest is history....just a thought.

In all honesty.. I can't even say "exactly" what and how things snapped, broke etc. at the time.. I only had two.
All I saw is my boat on the pavement, truck on the side and I was ready to cry.. I do know that my stern straps did brake.
I just checked. (I have another set.) Breaking strenght 10000 Lbs. Working load 3333 pounds. I was shocked that the stearn eye bolts didn't give first. It's also possbile the straps were draging on the pavement. Not sure..

Good point scarab.. Now when I go longer distances, I put the spare tire on the front and side, If something brakes,, and generaly the weakest point and the most of the load is at or near the hitch or the tounge, I have the tire hitting the pavements first. That might hold things up a bit, instead of metal digging in the pavement. I was pretty carefull trailering before, now I'm totaly anal about it.