I used to fight with old Cannon plugs for hours before I learned the trick with the dental pick

I was working on a Beechcraft King Air's nav system last month, and I spent almost three hours trying to get a stubborn connector apart, which my boss saw and just shook his head. He walked over, took a dental pick from his kit, slid it into the release slot I'd missed, and it popped right open (I felt pretty silly). How many other 'simple' tricks did you all learn way later than you should have?