I think people mean PSM, not PASM. Changing suspension settings (PASM) would have no difference on driving on snow.
3 yrs ago I bought a base 09 Box in Tucson. I flew down and by the time I left Tucson, it was mid afternoon. The plan was to drive somewhere past El Paso and then drive to Dallas the next day and spend the night with my sister. Part 1 of the plan worked fine as I ended up spending the night somewhere east of EP. However, the next morning I awoke to freezing rain. It started out light but was going to continue all day in the direction I was headed. I beat feet to get as much road behind me as possible but took care on overpasses. Suddenly at 11am things came to a halt. The road was totally ice covered and traffic was going 15mph. My newly purchased Box had a set of older Mich PS2 tires. As I crept along at that low speed, I waited for it to slide off the road due to the crown of the road. Didn't happen and even had stopping power on the ice. Drove like that for 3 hrs until the precip started to turn to snow on top of the ice. I wasn't going to make it to Dallas at that speed and I figured I'd already used up a day's worth of luck by mid-day, so I pulled off and called it a day. I was only 2 hrs from Ft Worth but not in the current conditions. Next day the roads were clear but the overpasses were sketchy. Spent the next day in Dallas as that storm cleared the area but had to leave the next day as another storm was coming thru the midwest and if I didn't make it home that day, I'd be spending 2 more waiting for roads to clear.
Bottom line, summer tires don't become totally inoperable in cold weather. The problem is people try to drive like it's summer and their tires won't perform to those levels. I've never been a fan of PS2 for street or track use, but they were stellar during my trip home. If texoma has to get somewhere, it is possible you just have to be very careful.
What it looked like when I left Tucson.
Next day at the hotel. The semi was stuck on the ice.
