Have you ever owned a BMW or a Merc?
**** me, they are beyond useless in the snow. I had 5 series estate and it was a joke, put some Vreidestein( spelling) wintracs on them and no problemo.
I had a C class Merc, during the bad winter of 2010, the only way I could drive it was by having a trolley jack, heavy tool box and four boxes of floor tiles in the boot. Without the extra weight it was, as you say, beyond useless.