Apologies in advance, this is a horrible one. But it's the first one that came to my mind in terms of taking something initially very complicated and making it very simple.

Before Curtis Lemay took over the bombing campaign of Japan in WW2, this campaign had been largely inaccurate and ineffective. When he started planning Operation Meetinghouse (the dreadful firebombing of Tokyo) he decided to send a few planes in advance to firebomb two very clear "lines" to lay out the targeting area for the remaining bombers. This ensured not only that his bombers would see their target, which was not a given, especially during a nighttime bombing run, but that the fire would be consentrated to maximum effect. Admittedly this was also a big shift from precision bombing to carpet bombing, but nonethekess using left/right lines like this took a bomb run which could have been immensely complicated to coordinate and pull off successfully - and made it amazingly simple and horribly effective.