What's something that people claim happens a lot, but you have rarely, or never, witnessed it?

[Machine_Elf]

@Bonum_Legatum

A cup of water, microwaved, that afterwards suddenly bursts into boiling. People say that it can even boil to the point of emptying the cup. I’ve seen microwaved water burst into boiling (when I added a teabag) - but never to the point where it all boils away.

It happened to my mom once. Not enough to boil it all away, but it did blast a fair bit of the water up on to the ceiling of the microwave. Fortunately this happened in the final seconds of heating, before she had a chance to open the door and put her hand anywhere near it.

I’ve also had it happen pretty badly on a conventional stovetop:

How to prevent explosive boiling?

Last year we installed an under-sink water filtration system. Ever since, when boiling water on the stove for pasta, we’ve noticed that the transition from “not boiling” to “boiling” seems to happen rather suddenly. I know this to be superheating, likely due to the filtration of particulates that would otherwise serve as nucleation sites and enable a gentle, gradual transition to a full-on boil. This had been merely an intellectual curiosity - until yesterday, when it happened so violently th…