Use breaks where possible. Even if they are only 5-10 seconds, it allows a bit of recovery and hand repositioning for players. However, try to avoid longer breaks that are in excess of 15 seconds. Breaks should especially be used with Easy/Normal difficultiesThis really depends on the song, and i feel this guideline may be misleading... Breaks should be put at where it fits (the vocal stops, a hard-to-map slow part, etc), not "1 min gone so we must have a break".
Also, for Hard/Insane players, a 2~3s break, a short draining time, or a slow-down part is probably enough for them to recovery/repositioning, break is not the only way to do that, so "break because we need a break" is quite weird. if a song rocks all the way i don't see the need to force a break somewhere.
For 15 seconds limit, as long as it's a guideline... fine then.
So a changed version here:
Use breaks where fits. Have a break at a reasonable place allows a bit of recovery and hand repositioning for players, then they can enjoy the map better. Try to avoid breaks that are in excess of 15 seconds so players won't wait too long for it. It is highly recommended to use breaks frequently with Easy/Normal difficulties