I was slightly disappointed in my BFG AT's this year hunting.
Coming down a steep grade on a logging road, compact snow/ice, 4 low, granny low, the back end of the truck let loose and swung around on me going about 2MPH, and there was nothing I could do but gas it for the bank before the end went off the cliff. Ended up sideways in the road luckily, with the front tires in fresh snow, and a bit of snow/ice built up on the downhill side of the rear tires from where they were sliding sideways.
If this was just a fluke, the only other truck out of 4 that ended up sideways in the EXACT same spot was driving a newer Dodge fullsize with BFG AT's on it as well. Only difference is that his were 12.5" width, mine are 10.5". Mine aren't siped, his aren't either I'm sure.
In about 4-6" of fresh snow, and a moderate grade uphill, my cousins 2004(?) F150 with stock tires (look like street tires of some type) easily went up, while mine would just stop in spots and start hopping as it found bits and pieces of traction. Never could get to where his truck was. Perhaps the Ford has traction control, but I doubt it. This same truck made it down between both of us with the BFG's that spun out on the other road. The shorter wheelbase probably made a difference, but a newer Toyota made it down before all of us no problems either, with non-aggressive tires.
I'm sure there are studies all over the place, but I suspect that on very slippery stuff like compact snow/ice (I couldn't even stand up where both of us spun out) the increased tread contact of the "street" tires is a plus.