It was an interesting watch for me, as we've just returned from a trip down the Hay River Track and acrosd the QAA Line. There were three of us, and yes, we were all towing.
I got stuck on the very first dune on the Hay, but apart from that, we had no dramas at all. Low tyre pressures (15psi front and Kamper, 18psi rear) sand was super soft as we had temps of 40deg plus!
It's funny some people's attitude towards towing across the Simpson. I know it is discouraged, bit it is not forbidden. We pulled into Poeppel Cnr, and there was a group of half a dozen people there, and the looks they gave us when they saw we were all towing could have curdled milk!!!
Having said that, i wouldn't tow heading the other way (East to West). The eastern faces of the dunes were badly chopped up, massive wombat holes and steep faces.
I dunno when the A4A boys did the trip, but I reckon they might have struggled a bit more than they showed, especially getting that van up some of the dunes.
Was a good watch anyway!
Cheers