Im looking for information regarding wiring single-family dwellinging units using "Romex"I was taught to "pigtail" ALL receptacles and switches out: 1- to make the finish side easier and 2 - if a receptacle or switch were to be removed from the circuit, by way of loose connection or the stab-in did not grab a hold and the wire came out, the remaining circuit down stream would remain energized. From my understanding this would be in Parallel.

On the flip side, the new company i work for does not pigtail anything out. We just stab all wires in the back of the devices, for speed.(its all about the money right?) So, using this method, if a problem occurred in a switch or receptacle as noted above, you would lose power downstream. Series?

Are there any Code articles that support wiring in Parallel vs. Series?