Somersault and Instant cast heals

[Houston009]

oGCD heals aren't spells. Silence would have to effect abilities too, which are most oGCDs even for physical jobs. AST only has one insta-heal as well which scales with target's HP. Think of that when you go to go silence them. WHM has Benediction/Assize/Tetra and SCH (Multiple)Lustrate/Indom/Fairy which is why silence is more effective on AST than WHM/SCH.

EDIT: Somersault doesn't silence, it reduces spell speed.