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Odds and Ends
No way out
8 6, 1:28am
I think you misremembered that advice.
If the doorknob is hot, that means the other side of the door is on fire, and if you open the door, feeding it fresh oxygen, the flames are going to suddenly rush into the room you're standing in.
You ARE supposed to touch doorknobs as a test, as in, before turning them and opening the door. You might getting a slight burn to your hand, but that's easily worth not incinerating yourself and anyone else in the (currently) safe room you're in.