Run with the Wind

While Ner'onok is casting [spell=121284] for the first time, move to the edge of the platform as displayed below. Then jump towards the other platform while he is still channeling [spell=121284]. After you land, you should see Tenwu lying on the ground. Talk to him and he will grant you Tenwu's Resolve. This buff lasts 2 minutes and grants 10% critical strike chance. Tenwu will also teleport you back to the original platform. Just finish the boss within 2 minutes and you will get the achievement.

Here are 2 screenshots displaying what you have to do.
http://i.imgur.com/K3ZbJ.jpg
http://i.imgur.com/xPvns.jpg

This is a personal achievement. Not having the debuff from jumping over (or being dead at the end of the fight) doesn't grant it.

A couple of other helpful tips:

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• Make sure to get a decent running start. I would suggest standing back further than the boss' original position and running towards the other platform. You will see a noticeable increase in your running speed if you do this and should easily get enough distance to reach the other side.
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• Line your jump up from a little left of the middle of the bridge. There is a bit more of an overhang on this side of the far platform, as can be seen in the picture posted earlier, so jumping from that side gives you a bit more leeway in case your jump isn't perfect.
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• Have your tank and any melee fight on the right side at the start (the boss is unmovable). This way, any [spell=121442] that is dropped won't be in your path as you jump. If you get the debuff, it will slow you down to the point that you will not be able to get across.
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• Don't teleport back at the wrong time. If you land back on the bridge as the [spell=121284] are blowing, you can get blown off the end of the bridge if you don't have the ability to keep from losing ground.
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• [spell=125146] is the buff needed for the achievement and it is applied as soon as [npc=64133] sends you back across the gap, so you have two minutes from that moment to kill the boss, and it may be possible for some party members to get the achievement and others not depending on the timing.
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