IO540,
I thought it was discouraged for pilots (students) to rely on a none-certified device? For sure, when I fly I have both my iPad 2 available in the back, and my 795 on the yoke but for instructional purposes, flying/intercepting a radial, tracking an NDB etc are far better done without a GPS *initially*.
I would also have thought that an instructor in the local flying ground would know the local VOR's and 'safe' radials to work to/from for the basis of teaching climbing/descending in IMC, maneuvering etc but alas no, not a single instructor who I ever flew with in IMC (4 in total, 2 for training and 2 personal checkrides for ensuring I'm doing nothing dangerous several hours into solo IFR flying) have ever taken a GPS with them.
But I totally agree with your other point, icing conditions are more a concern this time of year. I've experienced myself being in the freezing level and climbing through it and seeing +6 degrees on top, but in the descent you obviously get a supercold shell, and descending through moist air is always going to a factor.
I believe the CFI where I was based said that descending quick (cruise speed almost) should generate enough friction on the leading edge to keep it from icing in those conditions. Not experienced it myself yet - most of my descents have been controlled between 500fpm - 800fpm and nothing more when breaking into VMC. I guess time will tell ...
