[jamesqf]

Originally Posted by slowmover

This is a matter of forgetting acceleration, deceleration and any handling dynamics.

Nope, at least not two of those. Acceleration and deceleration depend on the total weight. Load plus trailer weighs more than load alone, therefore your A&D is going to be worse. (Braking MIGHT be a little better because of the extra tires on the trailer, but you've still got more mass to decelerate.) Handling is going to depend on trailer & load geometry. I'm no expert, but in my experience (which includes a spell driving logging trucks, among other things), in the best case handling with trailer is going to be worse than without. (This assuming the load is within the vehicle limits, of course.)

Think of a Tahoe with Dad, Mom and the kids. The cargo area is maxed out. There's a pod on the roof. And a hitch receiver mount cargo carrier with a box. Every aspect of utility and economy would be better with a trailer (and, obviously, a smaller vehicle could have been used in the first place).

Well, that pod on the roof isn't carrying the load in the vehicle, is it?

Now a counter-example, me taking the Toyota pickup out to get firewood. So I've got the bed loaded about cab high with logs, some hanging a bit over the tailgate, and yeah, it does squat the back end down just a tad (though not enough to be unsafe), and stopping distance increases, so I REALLY like to plan ahead. Now do you want to argue that I could put the same load on a trailer, more effectively?

Now after I unload the logs, I need to go to Home Depot for a couple of sheets of plywood. Again, you're suggesting that it's more efficient to hook up a trailer for the job? I don't think so.

Now if all you have is a car, then yes, a trailer might make sense for the occasional lumber run. Though in my case the car's an Insight, which won't haul much of a trailer, maybe one to haul a couple of bikes or kayaks.