Man once you get into complex wires I don't care who you are, that diagram is confusing as hell. Memorizing morse code a long time ago was a great bonus to the later levels though.
Complex wires isn't that bad once you learn how to account for the parts of the diagram that are deliberately confusing, but they're a lot harder if you only have one person with the manual. If you have 2+ people with the manual, one can get to work solving complex wires while the other helps the defuser with other modules.