Most runners are running because of [i]time[/i] efficiency. That's probably the right title depending on your operational definition of efficient. One size does not fit all here. "Efficient" is defined by the measurement: Efficient completionists aren't worried about time, but kills instead... Not skipping any enemies. 100% encountered enemies die at their hands. Efficient runners are looking for personal records on strike TIME completion. "Gotta shave 30 seconds off. Skip the stupid colossus and just run by it." It's all in the eye of the beholder. Use this weeks Weekly Heroic as an example. After you activate the console in the public area by the interceptors, do you: A) Fight every enemy in the first big interior chamber and then continue on, also killing every enemy in front of the bosses siege tank (public area)? Efficient mob killer = completionist. Or B) Run and jump past those guys to get to the lieutenant fight (darkness zone), then run and jump to boss area? Efficient TIME completion = runner. Certainly there are those that want to split hairs and kill stuff while they're running through, but killing level 28 cabal majors and ultras takes some freaking time. If you're stopping to down all those dudes you're a completionists.