The issue: Attacking from stealth does not reveal you unless you do actual damage to the target, no penalty for auto attacking a blocking/evading/invulnerable/blinding enemy.
Every stealth skill stealths you for at least 3 seconds (4 if traited) this is more than enough time to burn through most blocks/evades/invuls etc which usually have significantly longer cooldowns than stealth skills. In most situations this results in guaranteed damage to the target. The most common situation is where a ~permanent stealth thief keeps backstabbing you for potential 6-8k dmg until it goes through.
Suggested balance change: Make any blocked/evaded/blinded/invul etc attack reduce the remaining stealth duration by 0.5-1 second.
I think this change would force players to keep an eye on your target and promote skillful play opposed to mindlessly spamming attacks while in stealth.
(edited by Wile.5024)