He talks about 20 seconds, that's quite the length to hold 1000W+ on. Not to mention repeat it multiple times with 2 minutes of recovery, which is nowhere near enough for untrained or trained athletes unless you dedicate a significant amount of your recent training on sprints.

FWIW, I'm in a similar boat, my FTP currently is around 275W, granted I'm smaller (62-64kg), but I am still a long ways away from holding 1000W for 20 seconds.