[kiettyyyy]

Originally Posted by Al Skierkiewicz

The twisted wiring allows both wires to be exposed to external noise. Since the intruding noise is in phase as it passes through the wire, the twist will cause the 'in phase' noise to be cancelled at the source. Any noise that remains will also be in phase and that will be cancelled at the differential input to the transceiver chip.
Murphy is always lurking...

Make sure your wires have a consistent twist ratio, otherwise, it is possible to have the P and N signals arrive out of phase.

This is where you use those awesome formulas from your physics classes regarding the speed of light and velocity factors through copper transmission mediums.