Very true and excellent advise. What a lot of people don't know/realize is what they are talking about is actually called a Scotch-Lok; when you squeeze these onto the wire, whether it's solid core or stranded, is the connector inside actually cuts the solid core or the strands in stranded wire; and in some cases upto 50% of the solid core or strands are actually cut and now NOT conducting electricity which may cause a hot joint if a load is put on it.
Save yourself a headache and solder the joints. Any decent automotive mechanic will use a solder joint and heat shrink tubing/tape to cover the joint rather than a Scotch-lok.
The cutting into the wire(s) is part of the idea behind the scotch-lock operation. This insures conductivity, and also why they come in varying sizes so you don't use too small a lock on too large a wire and actually cut it apart. They are also not intended for use with stranded wire. If you are using stranded wire, the better idea other than soldering would be crimped on spade connectors and screw terminals.
If you have and end of a wire "NOT conducting", then you can not have a load on that end of the wire. Therefore, no "hot joint". You simply have a live wire terminated in an insulated joint, it's basically like putting a wire nut on the end of a live wire, it won't get "hot".
If you
do have conductivity, then the scotch lock would have to be providing a huge resistance in order for it to become a hot joint. At which point, it's easier to pull apart a scotch lock than it is to try and redo a solder joint that's bad.
And, using scotch locks in automotive environments is not the same as under a layout. The layout doesn't see the environment, the vibration, the contamination, the heat etc that a car will. It's an apples to oranges comparison.
You say save the headache and solder. Implying that a solder joint done correctly will yield no problems, correct? Well, install a scotch lock
correctly and the chance of issues is just as small as soldering. And you don't have to strip wire. And you don't have to use heat. And you don't have to worry about where the solder spatter is going to end up on you as you work over head. And you don't have to de-solder when you make a mistake. And........
Done
correctly either way will yield the same reliable results. You just don't have to do as much work with one of them
The Grotto is just behind there...