Pat,
you can take comfort in the knowledge that even if you had TKC 80's you probably would've got stuck a bit further down the road,just because it states M+S on the sidewall doesn't mean you're going to have top notch traction,far from it in fact,plus if theres ice under compacted snow you've no chance!,car tyres are very different,its amazing how much grip M+S marked car tyres have,but us Brits just don't get that,M+S tyres for both can be used all year round.