[OJFord]

Exact times are just fooling yourself.

I would say most UK microwaves have a time knob and up/down buttons for power.

[omgwtfbyobbq]

They're helpful for certain things, like cold bread (15s is great, 20+s is too much).

[OJFord]

What is cold bread, and what's the output, after these 15s?

Keeping bread in the fridge and want it very quickly room temperature for a rush sandwich? Does it really need to be in the fridge?

[omgwtfbyobbq]

Yes and yes. It doesn't need to be in the fridge, but certain kinds go moldy much slower there.