Those are loc-rite or spartan lockers... Detroit have gears that spool to tighten and cause the wheel that's spinning slower than the driveshaft to spin at the same rate as the driveshaft - that's also how you can go for a ride if you let off the gas while travelling down hill on a rain-slicked surface. Detroit says 3 -10 revolutions before it's locked tight. Ratcheting... those are loc-rite/spartan locker type gears. They won't let the other wheel spin slower than the driveshaft, ever - they also make the distinctive noise, and cause great understeer if you stomp on the throttle in a corner.
The other thing about detroit, if you do lock it up in the manner I described above, you need to drive backwards at least 3 tire revolutions to get it to unlock (because it will not allow the tires to roll forward). It took me about 10 minutes to get my wits back enough to remember that...
I'm one of thousands who've learned this and all their stories share the common elements of downhill, rapid deceleration, slick road, short wheelbase, and traveling backwards. My story has a "nothing damaged but underwear" many others, not so much. I was driving down US 26 into Portland - a place called Zoo hill (because the zoo is at the top of the hill). I was driving a 74 Blazer on 44s and I was booking. It was rain slicked. At the tunnel (bottom of the hill and the freeway makes a bend into the tunnel), cars were dead stopped. I let off the gas and was immediately travelling backwards at 60 mph. Rear tires were locked up and I was the meatsack in the driver's seat. It stopped with the rear bumper about 4" from the poor lady who was stopped because of traffic. Honestly, it's why I tend towards spartan or loc rite lockers now... I don't ever need to repeat that spin.
as for steering. if you really run into trouble, you get your spotter to unlock one hub.