Yes i have some reflect damage, but on the paper that look awesome, but in pratice you can do all of those thing, you don't have the time.
situation 1 : demo on something (you can't charge him).
You are going on him, you lost 20% while going to him, then you are at him, trying to KB him, but no chance he KB you, then when you are KB, burst you has hell 30 - 40% of you'r life, you stand up, he is far away.
So you charge him + snare.
He use purge (generaly demo got an anti root/snare and the anti cc).
Then he go away and he can still root you, stun you etc.
No chance at all.
Situation 2 (the one i use and that work not bad against 1 v 1 in good place (without rock etc, not in mini).
Be hide, Frenzy, use volcanique rage, the heroic flag, the tactic, charge him + snare (for be sure he don't evade the KB aoe) (you can active anti cc too to be sure you will not be stop after he stand up).
Use a feint V on him, then another combo if you have time, and OLP, usualy he lost 80% of this life (except he is pvp 10 / t4.. )
Now the first thing he will think is KB/stun, so be ready with deflect damage and return attack.
That should kill his last HP.
And btw remember those darkness heart let them resist to fear and stun. 15% i think, with some AA he go maybe 20 %+.
So this is poker face if you try fear him and that don't work