What is an inline splice?
Well, if you work with any type of electrical wiring, and need to join 2 pieces of wire you have 2 choices, pigtail or inline
Pigtail splices are when you hold the 2 pieces of wire, one end going up, the other going down, and twist their stripped ends together.
The issue with pigtails are...
1) They are ugly
2) They redirect the wire 180 degrees, so going from point A to B requires a sharp bend
3) After making that sharp bend you have this chunk of pigtailed wire flopping about, usually with a nice wad of gooey black tape, and sometimes a zip tie to act as a strain control
4) Since the connection is 180 degrees (or going the totally opposite direction) without some form of strain control, all it takes is a stout yank to sheer the connection (even with solder), altho honestly this is an extreme con
The pro's of pigtail's are
1) they are "easy"
Inline splices is where you take two pieces of wire, and join them in a nearly seamless extension of wire
Inline the issues with inline splices are ...
1) the are "hard" (and I claim shenanigans!)
The pro's of inline splices are
1) They are almost invisible, and look professional
2) They do not redirect the wires natural flow, going from point A to point B is just as simple as if you had the chance to place a wire from point A to point B
3) Since there is no bends in the wire, there is no chunks to manage, which is especially handy in tight situations or where you do not have a lot of wire to waste (ie: repairing wires in a vehicle)
4) they are really strong, even without solder bonding them (keeping in mind that they are not permanent, stress and vibration will eventually disconnect them without solder)