In Matt Mikul's excellent new randonneur blog, he wonders about whether to sleep on the upcoming SIR 600km brevet. He notes the advice in the RUSA handbook that a sleepless 600km is key preparation for riders planning to ride a 1200km. This has always been one idea in the excellent RUSA handbook with which I disagree. I differ for two reasons.
The first is personal - I have completed 7 1200km brevets (including the 1400km London-Edinburgh-London) in 8 attempts. I have also done 13 successful 600km brevets and none have been without a sleep break. So I know from personal experience that it's certainly possible to be successful on a 1200km brevet without a sleepless 600km brevet.
The second reason is that I believe that taking a sleep break on a 600km brevet builds three key skills for a longer brevet.
The first skill is managing your time, by pushing on the road and at the controls, to build a cushion that permits a sleep break. I find that thinking about carving time for sleep provides a good focus for the first 400km or so to the sleep break.
The second skill is simply practicing the logistics of a good overnight stop. It helps to learn how to combine efficiently in a few hours some pre-sleep food, a shower, sleep, a post-sleep breakfast, replacing and repacking gear, and maintaining the bike.
The third skill (really more experience than skill) is to learn the feel of starting again in the morning - getting the tired body moving again and revving it back up to good riding form. When doing a 1000km or 1200km, confidence is increased by knowing that you've done that before.
Unless you are one of the talented few riders that can blast through a 1200km on no sleep, learning overnight stop skills on a 600km is excellent preparation for what you'll do on the 1200km brevet.