Skadi is one of a very small group of Heroic bosses who are still (as of patch 3.3) able to cause noteworthy problems for a well-geared player group, and he is to be respected on that basis. This fight is relatively complicated but not difficult once learned. The single most important thing is to keep moving around; Grauf's frost breath, and then Skadi's whirlwind, mean that characters who remain in one place, focused too purely on their rotation at the expense of all else, will likely end up dead fairly quickly.