From Dante’s mouth:
Here's the official DC methodology, which is slightly different from Dr. Clay's version:
Say you're getting ready to do barbell military presses. After a few warm-up sets (there's no specific guideline for this, according to SM; just do what you need to do to get your joints and muscles ready to work), you load the bar with a weight you think you can lift 10 times. Do as many reps as you can with perfect form until technical failure, the point at which you can't do another perfect rep.
Put the weight down and take 10 to 15 deep belly breaths. "The deep breaths help supply the body with oxygen and let you partially recover," SM said.
Pick up the weight and do another set of perfect reps until you once again reach technical failure.
Set it down, take 10 to 15 more breaths, and then bang out a few more perfect reps.
Your goal is to do between 11 and 15 total reps. "If you get 15 or more, you know you'll have to increase the weight the next time you do the exercise," SM explained. And if you get fewer than 11, it means you need to either lower the weight or shoot for more reps the next time.
To make it even more brutal, some advanced guys do one static rep to extend the set. Continuing with the shoulder press example, after you set the weight down for the third time, you'd take 10 to 15 more breaths, pick it up, and then hold it in a "power position" (elbows slightly bent), with the muscles under tension for 30 to 60 seconds. But this is only recommended for advanced guys.
Not every exercise uses the rest-pause technique. "For safety reasons, we don't do it on quads, calves, or back-thickness exercises like deadlifts, rack pulls, or bent-over rows," SM said. They do straight sets for those exercises.
Not every rep range is between 11 and 15. On the Widowmaker, for example, you do an all-out set of 20 reps on the squat with a heavy weight.
Even on rest-pause sets, the reps will end up between 20 and 30 for biceps and triceps exercises, and if you switch to dumbbells over barbells or machines on compound exercises, you'll also increase reps.
The reps may be high, but that doesn't mean any aspect of the training is easy. On DC message boards, a regular theme is the need to work hard enough to elicit a positive response from each rep.