Cobra Trailer Emergency Brake Experience

Agreed.

The only "issue" I have heard regarding chains as a safety device..... going down a long hill, trailer was not properly attached to car, trailer came off ball, car slowed, trailer tongue went under car and punched a hole in the car gas tank.
This was likely early 80's.

Yes, sorta heavy and long wheelbase tow vehicle lessens the issue of a glider trailer behind it. Part of why I bought a wagon in 98 for normal driving and glider towing.
Granted, a ASK-21 in an enclosed trailer means you really need a big tow vehicle (or lessen your speed).....my wagon was OK until an "oh poop" of an aggressive driver on a long downhill at speed cut across 3 lanes of traffic in front of me.....yikes.....