Maybe it would help if they gave Rescue a cast time and an animation over the targeted player's head. That way, the targeted player has time to react to their position being changed, and they can use an anti-knockback skill to mitigate it if they want. It would require more foresight on the healer's part, but it would still be perfectly usable in organized group scenarios. Also, giving the ability a more noticeable spell effect can help illustrate the healer's mastery when they're using it well.