The inability to use heroic leap in 90% of places.

[kirasano]

Ozruk in Stonecore. I thought: I'll use Heroic Leap to move away from Shatter.
"no path available" - BAM! Dead...

Really? You have to target on the ground not the wall.

Man I'm not retarded. I know how this ability works. So remove Your sarcastic tone please.
You can feel lucky if it didn't fail on You yet. Sonner or later You will see "No path available".
And as per comments - there is more people commenting on this ability not working properly, than people saying it works perfect. This does tell something.
I wish Blizzard could fix this.

[Electromatt]

its not that bad...
I use it when rogues do the "you cant charge me and cant hit me" bullshit. just target behind you then charge em.