I did an HRHS course through ALTC Bandiana. Very intensive. Soldering had to be spot on to earn a pass. Army instructors were lethal. Passed though.Crimp sizes are generally colour coded. I have yellow, red and blue, all different sizes respectively. As Col says, using the right size crimp works. Don't discount soldering, though. The best join can be a crimp with solder wicked into the wires to creat a solid block at the crimp.
As for creating a spike when withdrawing the soldering iron, well, that's just bad technique. It's a shame the Air Force stopped training High Reliability Hand Soldering. I was one of their last graduates as a technician, not that it makes me an expert.