Last weekend a Massachusetts woman hiked to the top of Mt Jackson under cold windy conditions and became disorriented. She planned to hike out and back on the same trail but lost the trail on top of Jackson and could not find the route back. Fortunately she was able to get service on her cell phone and called for help.
Although search and rescue personnel were not able to find her until the next morning when a Black Hawk helicopter pilot and provided the ground searchers with her location, she kept resonably warm by walking in circles throughout the night. She walked out on her own with guidance from the searchers. Whether she will have to pay the cost of the rescue is under consideration.
When you look at this Google Earth picture of the area around the top of Mt Jackson, you get an idea of what she was facing. The darkness of the green indicates dense evergreens probably spruce. Near treeline that means small thick spruce with spruce traps. With deep snow you don't want to be off trail in spruce traps as it can be exhausting. I've been in situations where I've used ice climbing tools to hook trees to drag my body out of hole after hole and taken an hour to travel 1/4 mile. It's probably wise that she stayed put.
On the other hand its not a given that you'll get cell phone service in the White Mountains. If she had been on the North Side of Osceola, she would not have been able to call out. Since it seems that bush whacking, is not a good option it seems to me vital to either turn around when there is a chance you might loose your way near tree line or invest in GPS technology to be able to find the route you came in on in difficult conditions.
The way I invision using the GPS to get back out is to be sure that it is turned on whenever you can conceive of loosing your way. Check that there is adaquate battery life at that point. Have the GPS configured to log your track and display it to the map page. Should you become disorriented turn your body is the direction where the display arrow points toward an appropriate point in your track log in your track log and walk that way until you get there. Repeat until you find your way out.
Unfortunately there is a steep learning curve and expense with GPS. In my opinion you are better off without a GPS unless you buy something of high quality and are willing to spend time learning and practicing its use. I believe that the GPS should have:
o A high quality processor that does not loose satelite links in dense cover and in canyons.
o A map display mode that shows were you have been and an arrow indicator that shows the direction that you are currently traveling.
o The display be viewable in difficult conditions.
o The controls be useable with gloves on.
o The direction indicator controlled via an electronic compass built into the GPS.
o The ability use a spare set of batteries (lithium in winter).
I have had four Garmin GPS units that I've used for navigating in the backcounty of which I currently have three.