Prompted by this question about the sleep spell and waking those effected by it, I've been wondering whether it has been commented on officially.
The issue of a chain of dependant events all occurring in the same six seconds must have been noticed before now. In the case of the question that prompted this five out of six goblins are put to sleep and then wake each other up as their turn comes around, Goblin 1 (who is awake) uses their action to wake up Goblin 2, Goblin 2 then wakes Goblin 3 and so on until Goblin 6 is woken and can attack. That attack relies on five other actions already having taken place.
Any official books or even Jeremy Crawford's comments (I know they aren't "official" any more) would count.