Honestly the first cluster sets I did called cluster sets was from Steve Shaw, and his was like a minute or two rest, 3 sets and you picked the rep range. It was fun, I picked lower rep targets for heavier movements, and higher rep targets for the stuff I wanted to go lighter on. So I might do 35 rep target, and hit 14,11,9, or higher reps might be 45-60 reps. Honestly, any way you want to cluster them and or use the term works. Whether that is, DC and RP sets, MyoReps, muscle rounds, all basically the same thing just someone else coined the phrase or made a small adjustment and renamed it for notoriety. The bottom line is they are a method to increase training intensity, and density, while allowing for more approaches to failure with less total volume required.