Approximately after every second Frost Breath, while she is on land, Sindragosa will pull the entire raid next to her with Icy grip and start the 5-second cast of Blistering Cold. The spell does very high amount of Frost damage, so everybody should run out of its 25-yards range.
So here is the trick:
Look at the timer of Blistering Cold and when 2-4 seconds left 1 man must position himself as it's shown on the sreenshot. It's rather tricky to stand in the right place so no one will be griped to her (sometimes 3-5 ppl can be griped if you srewed to stand right) and all melee must stand as far as they can while they still can hit her
On the second and third screens you can see that all raid members still stand where they were before the grip
Video with two partial avoiding and a full avoiding icy grip =))