As a prominent Voidwalker with Nothing manacles for a very, very long time now I can attest that Scatter grenades always killed you at full health, that's nothing new. It should be noted that Voidwalkers have noted that since the Warlock changes Scatter grenade does now have a slight bug which means the grenade will not shatter upon impact and instead bounces. This means that if you are on target with your throw, it allows your enemy to move away before the grenade scatters. Supremely annoying and actually made me change to run Sunsinger with Sunbreakers on my Warlock in PvP. Sad times.