I've said this in another thread. What does worry me about winter tyres is that there will be numpties out there who won't adjust their driving style to the conditions, because they've got spangly new snow tyres....
If you drive round like it's a hot summers day in the ice and snow, you're going to come a cropper whatever you got on your wheels!! 
I think the numpties of which you speak would be driving in exactly the same manner on summer tyres - the only difference being they'll probably fall off the road sooner, but at no lower speed.. heck, it seems to me most people drive with scant regard for the conditions anyway :-/
It seems to me (having read threads like this on every car forum I frequent) that opinions on winter tyres are almost entirely polarised into:
1) I've never needed them before in X years, you're all wasting your money, nobody needs winter tyres in this country!
2) I tried them and they're amazing, you wouldn't believe how much more grip & safety you have.
And ne'er the two groups shall meet..

Not knocking either view - I was firmly in camp 1 until this year when I figured that, in reality, it's cheap insurance on a car I intend to keep a while - £400 or so on a set probably amortizes down to ~£100 a year, and should save me 1/3rd of a years worth of wear on the 'normal' tyres, somewhat offsetting that £100.. Which at this point, is about a tank of fuel..