How do you handle gently in the field when the simple act of transporting them could induce ventricular fibrillation? Just go for it and defib as required? That alone says EMT's and certain specialized equipment are required for transport -- maybe not so simple.
You handle as gently as possible under the circumstances. One thing to keep in mind is that when the victim is severly hypothermic, if you can insulate them (gently!) from further heat loss, they are stable for quite a long time. Rather than "go for it", it is generally better to wait for more resources so that you can move them gently. Get lots of people and whatever gear you need. Pack out a smooth trail in the snow. Get a saw and cut away vegetation in your way. Get a helicopter.
The bottom line of course is that we do the best we can with what we have. But you can afford to take some time and get help.