Yes, that would make sense. Take into account though that for many people most of their gym time is overhead, especially if they don't have equipment at home. A large % of time is taken up by getting to and from the gym, getting changed, taking a shower, setting up the right weights on the bar and doing warm-ups, cool-downs & stretching. Because of this, adding an extra set doesn't mean that you'll take 2-3 times as long in total. Determining whether the faster gains you get from doing the additional sets are worth the marginal time depends on a number of factors. If you have plenty of time available for workouts, then do the 2-3 sets and reach your goals faster, if your time is extremely constrained, then the extra 20 minutes per workout might not be worth it