Strength and skill under fatigue, that is the point of an EMOM, hence why the ones you do at this gym suck!
Push the load to be a significant challenge and pick a number of double unders that affords you little rest.
Then, just suck it up for 20 minutes…
CrossFit Cardiff WoD
Every minute, on the minute, for 20 minutes:
Odds: 5 Power cleans (80/60kg)
Evens: 30 Double unders
Specialty
Squat snatch
3 - 3 - 2 - 2 - 1
Accessories
Hip extensions
10 - 10 - 10 - 10