As someone with extensive scarring on one arm from a water burn I'd prefer it if you didn't put things like this out there.

Fast reflexes won't help your hand to recover from a bad burn, they won't prevent it either, your hand is much too large to be immersed fully and retracted before substantial damage will occur.

Maybe for a fingertip, but I wouldn't try it with a full hand. The water stuck to the hand will take time to cool down no matter how fast you remove it. Unless you're just saying second degree burns don't count as major damage...