The scientific approach- which no one ever does- would be to try with the duals, then take the duals off, weigh them, add the same ballast in iron, and go again. I bet in those conditions the pull would be the same, maybe better without. I was told many moons ago that, in dry, firm conditions, a long footprint was better than a wide one. YMMV

Watching the plowing videos from HCOP, the guys with a land-side dual were having trouble with grip in the stalks. Tomorrow, when they go back to plow the whole squishy mess up again will be a different story...