I've found this item on the Subtleties page https://github.com/ethereum/wiki/wiki/Subtleties:
If contract initialization returns an empty array, then no contract will be created. This allows you to "abuse" contract initialization as an atomic multi-operation, which might be useful in some protocols where you want to do multiple things but you don't want some of them to be able to process without others.
Can anyone explain what it means? In particular the 2nd sentence.