This exercise is an example of how cable work has some advantages over a barbell in that the loading curve matches the strength curve, so there's constant tension on the delts from start to finish.
The other advantage is that most of the initiation of the movement comes at the shoulder joint rather than the elbow joint. The synergy between these two components makes this movement an awesome shoulder developer.
So you spend maybe 5 or 6 hours a week in the gym. How much of that time is spent snapping towels or playing the soap dish game in the locker room? If you plan just a little and cut out the wasted time, you might actually build a decent physique.