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I have been impressed with the TC and active stability features of my Teslas. I have tried to get them to spin, slide, etc. in wet and snow (under controlled conditions, of course) but failed completely. I did have one event where I was traveling up I80 on a wet curve and the car started to slide but quickly corrected itself (with a few messages on the screen) before I could react.
So, I don't know if the Tesla Semi would have prevented this but I think the chances of it are lower than a "dumb" semi.