Unseen Strike hits in a cone, what my group does is, around 2 seconds before it hits, start to stack up. Identify who is the target, and everyone stack behind them. There will be a very faded version of the boss, ready to strike, and by that you can see where it's about to hit.
Tanking/moving the boss was a non-issue for my raid. Just move them after an Unseen Strike, and when there are too many cyclones around the boss.
To be honest, the only problem my raid group had was surviving the cyclone phase, the first phase was simple. Range DPS spread out, melee always stay behind the boss. When the boss does Windstep, make sure your melee don't go crazy, wait for the boss to come back to his original position. Your healers should not be OOMing in Phase 1. Are they over healing? Are they geared enough?