It has nothing to do with timing - it's resistance. Yes, even wire has resistance, but as stated in short runs for speaker hookup, using 12/14 Ga wire, there is no noticeable affect.
Practical example:
If you have several extension cords (typically 16 ga), try connecting them all together to a length of say 100 ft or more. Plug it in an AC receptacle. Measure the voltage at the receptacle and at the end of the cord. You will see the voltage has dropped. Does that mean we can't plug appliances into it. Absolutely not, their designed to operate in a range of voltage and you won't even notice a difference in the appliances operation. If you increase the gauge of the extension cord wire (16>14>12, etc), we will reach a wire size where the voltage at the end of the cords is the same as the receptacle. The other way to restore the voltage level at the end of the cord would be to stepup the voltage at the receptacle to accommodate the expected voltage drop.
So, to relate this to HT. if we use light speaker wires that brings the wire resistance into play, we must add more power from the rcvr to make up for the added resistance. Obviously, not efficient.
Bottomline: Use at least 14 gauge copper wire for typical HT speaker installations.