I was fascinated as I read this thread. Its interesting how different people look at things in different ways.
I live in an area where we treat hypothermia year round. In listening to the comments and suggestions made previously, I can only speak to what I would do.
After assessing the mechanism of injury and noted the time frame to when you can get this person some place warm leaves you with a tough decision to make.
Rule number one we teach all our emt students is you NEVER cut a down coat in an enclosed enviornment. That being said, if it were me, I would go ahead and cut the sleeve to access the arm and obtain an accurate bp. Afterwards, I would then close the sleeve back up using duct tape. It would hold the sleeve together and keep the pts arm warm and dry, while giving us the ability to reassess the bp in the future.
We rednecks love duct tape!!!
I think we all agree that how far off your transport is makes the decision what to do. If you are out in the wild, you might have to do more before you can move or make decisions than if you can pull your truck up curbside and toss the snow shoveler (is that even a word/) in the back. But the scenario keeps morphing, so of course the decisions and priorities do as well.