an interval workout riding at high effort for 20 seconds then normal effort for 40s, repeating until I reach the top of a climb. I then coast back to the bottom and do it all again between 3 and 5 times. The only option I can see is to create these 20/40 intervals and then manually repeat the workout 3 to 5 times.
If I understand you correctly, that's exactly what the Repeats in the Workouts editor, that travis.vitek suggested 8 years ago, are for. Or did I misunderstand?
There is a way to do this. Create the longer duration (outside) interval as a repeat. Don't add any information inside it yet. Then create a second repeat. with the shorter duration interval inside it. Add details into this. Carefully drag the second repeat inside the first repeat. Finally, you may need to remove some of the unused steps from the first repeat. In my case I removed the blue section and kept the recovery. Adjust the number of times each one repeats. Here is a screenshot of my 5 x 8 repeating interval workout.
