if you are driving on mostly clear, snowy highways in which 50mph is a manageable speed, doing so in 2wd is just as good.

if you are trying to plow your own path through arctic snow swept streets, 50 mph isn't really all that safe (read as: dumb)

if you are in 4wd at 50 mph and hit packed snow/ice you will slide only slightly less violently than if you were doing 50 in 2wd....

just leave a little earlier and dont risk your ride, your life, or the lives of those around you. while you may be the baddest cat in town, no one will be impressed at your 50 mph 4wd action when you are sliding door-to-door off the highway with the other vehicle you were trying to pass when you hit the ice patch...