Salt in the wound & Oil on the fire - why (don't be evil) and when (never)

• Salt in the wound (never) => Vinegar or alcohol in the wound (might be right)
  => Healing oil or water in the wound (Ok)
• Oil or alcohol on the fire (never) => Vinegar or water on fire (might be right)
  => Water on the fire (Ok)

Conclusion: Please don't be evil and please never put "Salt in the wound" or "Oil on the fire"!