That Bel Air was an 11 year old car at the time and was an ex-cab (another words the shocks were shot) the car swayed too much which magnified the uni-traction characteristics. I used this magnified example to show the effects of single traction. I've owned cars that had single traction and converted them to posi (a 7.5" uni will become a 7.625" posi for example which are the units used in F-body V8 LT1/LS1 Camaro/Firebirds and certain S10s).
Try driving up hills in rainy or even foggy San Francisco with UniTrac; it's not going to happen.
You know you can say what you want about my driving skills but I have no trouble saying to you that if you want experience driving POSI then you have to learn sometime however this doesn't reflect directly on your comment because you were refering to my time driving non-posi unit so I won't take offense. I'd hate to see what you'd have to say if I did a few posi fishtails but perhaps you would have the opposite say such as the impressive smoothness of the slick and predictable slide I muster sliding my 94 Impala 3.08:1 8.5" Posi around a corner in the rain with column shifter in 2nd which overides the 4L60-Es torque converter's decision to uphshift or downshift; butter smooth with the back end out one end for a 1/4 block by modulating the throttle input.
Oh the time I bought a 1978 Dodge Monaco 4dr which was originally sold from Century Motors in Winnipeg complete with FULL WINTER PACKAGE. Yes, folks, a true WINTER CAR ordered as such with a very large block heater AC loom attached to one of the square grilles (think Rosco's Monaco) powering on the other end no less than 4 things: 2 heated block plugs, 1 battery warmer complete with hug-the-battery electric blanket and an AutoPar cabin heater mounted in the passenger side kick panel. Oh and ofcourse the all impotant item required for such a snowy region which sees dumps of snow for months and -40 degrees C/F (yes the same number for both units of measure), a 9 1/4" 3.21:1 SureGrip Limited Slip differential. I drove that car in the snow for quite some time before I decided to restore it. She would cut through snow like hot knife through butter. There was no where she couldn't go in a snow blizzard. I drove her on 5 hour journeys through canyons and mountain tops with nothing but me and snow/sand/salt splashing semis next to me and the SureGrip grabbed with might. Anything single traction would not have been able to last 5 minutes with one wheel spinning and GOING NOWHERE.
I remember the time it poured snow in Vancouver with lightning bolts. Intercity traffic was locked in accidents and stalled cars everywhere including front wheeldrivers. I hopped into my MoPar with confidence and proceded down very steep grades that would normally be blocked off. Hitting my police duty brakes (was not a police car but was ordered to have winter HD specs which seemed to include such niceties as double serpentine belts, suspension to handle the SureGrip, etc.) on and off slowly down the hill yielded me to safety. At one other point after passing plenty of stuck SUVs, the sheer icy terrain permitted me to go close to a curb with millimeters to spare. Making love to my LSD I eventually nudged my way out of the curb's dead end and proceeded once again (remember in these instances a bag of kitty litter in the trunk helps wonders if you have a land yaght from the 70's with no weight pushing down on the axle unlike todays RWD cars with exception to Ford Panther-bodies) which have plenty of strategic weight in the C-pillar zone and back resting over the axle). I got stuck one more time before arriving home (for a minute) and thanks to posi spining them up at both ends,it didn't take the Monaco long to grasp the slush on both sides and spit it out like shark's teeth biting jelly.
At one time I had a 1978 Malibu on the road with 7.5" UniTrac and it started to snow buckets and I needed to be at my workplace a 6:00AM and there had been no snowplows yet or traffic to de-virginize the freeways and roadways. I borrowed my girlfirends '95 Camaro Z28 which I optioned with the 3.23:1 7.625" Posi (as opposed to the 2.73:1 version). I said to her that I needed get to work on time and the single trac 'Bu with P235/7014s was going to be a nightmare. I got the Z that morning and drove through all the fresh thick snow (with stock Goodyear Eagle RS-A all-seasons) and laughing with excitement the whole way with the ASR (trac control) OFF. I felt like Dr.Zhivago enjoying a perfect trip without flaw going home. Once on a seperate occasion the Z got stuck in a snow pile. I had told my girlfriend how useless the Bosch 5 traction control would be of she got stuck like we had that one night. Ofcourse all the Bosch trac control does is pulse the brakes and retard the LT1's timing; all useless in this situation. All that happened with the ASR was that it retarded the timing to practically nothing;ever heard an LT1 do nothing in the RPM range when hitting the pedal? Try getting stuck in the snow. I showed her these effects that I had told her about that could happen and then I switched off the TRAC CONTROL and rocked the 4L60-E tranny back and forth 4 or 5 times and voila, POSI comes through again; I love predictability. If that was a open diff, you'd either be calling AAA or be slaving away with salt, flexible tire ramps, shoveling, etc. it's like having 1wd!
Many times with my LSD cars if I was in a tight spot and parked on tons of snow, I would apply this technique. Instead of putting the car in reverse (such as was this example that I was in at a friends driveway with car part in front of me) and letting the posi's dual grip push the car slowly to one side (like towards a concrete fence in my case!),I pumped the gas pedal about 12 times in reverse but only 1/8 away down each time (ah the glory of a TORQUE DOWN LOW V8) and a few seconds later I was clear of the potential quarter panel damage of the Z car's pose to dual trac into the concrete. Hence if you know how to utilize and master LSD you will feel free like a bird and buy nothing but LSD cars!
The United States Air Force has about 20 at any one time REAR WHEEL DRIVE POSITRACTION cars designated to be used as U2 SpyPlane chase vehicles in California and in Europe (and sometimes in times of war in other places of the world through sandstorms, etc.). These vehicles must meet 2 standards. Be very torqey off the line and be able to accelerate radically fast to speeds in excess of 100MPH in order to chase a U2 SpyPlane on take off or when landing (reason is because these aircraft are very long and wide and are large gliders and can not land without on-the-ground data being transmitteed back by another U2 pilot behind the wheel of one of these chase cars chasing behind sometimes closing in at about 60ft. And yes in parts of Europe where these bases are it is rainy and cloudy with plenty of mist on the ground. Such cars have included the new 6.0L Pontiac GTO, late 90's Camaro LS1 cars, Fox-platform Mustang Interceptors, non-stock El Caminos (with big blocks) and Ford Station wagons with big blocks. No room for error, you wipe out and you could lose a plane and human lives. Needless to say, handling a posi with a torquey V8 accelerating in the wet at speeds equaling the aircraft you are chasing suggests that you can indeed get to your school, store, date, bank, beach or wherever you are going in rain, sleet, snow or mud in your posi trac vehicle.