3 of my friends are electricians and have seen it happen before. yes some of it is paranoia but some is also common sense. when a circuit is overloaded no matter how much it trips a breaker. if that breaker is a higher amperage than what the wire its connected to is rated for, you are overloading the wire. regardless if its 10,000W or 1W.your all just paranoid, your house will not burn down, as long as your not overloading the breaker by running 10,000wtt of lights
http://www.buyerschoiceinspections.com/Overloading-Electrical-Circuits
http://electronics.howstuffworks.com/circuit-breaker.htm/printableOverloading Electrical Circuits
Electricity has enriched our lives. Despite the many benefits, electricity can also bring danger -- the most common being house fires. It is estimated that over 40,000 residential fires are caused by overloading electrical circuits every year in the United States. Causes include arc faults, short circuits, or overloading of electrical circuits.
The circuit breaker is an absolutely essential device in the modern world, and one of the most important safety mechanisms in your home. Whenever electrical wiring in a building has too much current flowing through it, these simple machines cut the power until somebody can fix the problem. Without circuit breakers (or the alternative, fuses), household electricity would be impractical because of the potential for fires and other mayhem resulting from simple wiring problems and equipment failures