Rescue is plenty useful for when someone does the mechanic wrong, it effectively saves them from their demise (should said mechanic kill that person). Of course you can use it to troll but it is still on a large enough cooldown to stop that from happening nonstop. You could argue that there are mechanics that people don't require saving from as they can withstand the hit...and that's fair but is it worth the chance of death? Death gives you a stat down debuff...