That is true. While I don't recommend it to people that are not use to
working with electricity, a trouble shooting practice is to subistute a lamp
with for the fuse or breaker. If the circuit is suspose to be open the
light will not burn. If you put in a 100 watt bulb in a 120 volt circuit

Of course, the sensible thing to do would be
to shut off the breaker, and test continuity from the nuetral to
the hot, but that requires a hunk of equipment that costs
several thousand pennies.