I cringe every time I hear of someone "splicing" into an existing circuit. My visual image at worst is someone stripping back insulation in the middle of a wire and wrapping the end of the new wire around the existing wire. Second worst are those scotch lock connectors. It's a potentially dangerous way of doing it. Just my personal feeling ....
You cringe.... Try being the guy who actually has to come in a fix these absurd practices....
This was just last week:
Note the melted/deformed black and blue wires near the wire nut from high resistance... In the background we had four 1GA wires bolted together and the nut was loose. But hey it was covered in electrical tape.
The small red wire entering the black tape was a bilge pump wire that was simply twisted around the mass of battery cable lugs, no terminal what so ever. This is a circuit that demands close to 550A every time the bow thruster was kicked on and over 800A when the motor was started.
The person who installed the battery bank fuse stacked the smallest loads on the bottom and the heaviest load on-top of FOUR smaller loads. It got so hot that the Class T fuse holder physically melted!!
On-top of all this welding cable was used and the jacket literally fell apart crumbling in the bilge. It was leaking DC current directly into the bilge water. A simple alternator upgrade turned into three days of re-wiring all the heavy battery cable because someone cut corners and did not use proper wiring techniques........$$$$$$$$
