Fir the single cut wire that's the best way, I was more talking about a full splice. using a PC is less bulky than three individually spliced and shrink tube covered wires.
I've been thinking about designing a dedicated "splice PCB" in Easy EDA that people could upload to JLCPCB and have made cheaply. It would have larger holes than the Hansen pin strip PCB that would make inserting the wire easier and a strain relief hole at each end you thread the wire through first before sticking it into the solder hole.
EDIT: Got off my butt and did it. The leads thread through the cutouts on each end and the wires are inserted into the plated slots in the center and soldered form the other side. Then cover with shrink tubing. The PCB is 10mm long x 7mm wide. Going to order a batch form JLCPCB to see how they manufacture, if they turn out ok I will upload the gerber file for anyone to use. Something like this only costs a few bucks to have a couple dozen made.
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