The two barbell movements are what stand out when evaluating this workout. Which means that's where a lot of the work is going to be done. Not necessarily in terms of time, more in terms of muscle fatigue. The rope and the row is where you can take a second to breathe and get ready to attack the next barbell. Breaking into sets early will help offset fatigue, so be smart about the breakup strategy and get to work. If you want to practice double unders for seconds as opposed to reps, 90 seconds will work.