"Reporters on all channels seem keen to imply this was a just a reminder - not meant to cause mass casualties - I'm not buying this line"
...there is also the scenario of creating a diversion then hitting with the real stuff in all the confusion.
Psychologically, I can see the appeal of an action that says "See - just two weeks later and we hit you in exactly the same way. This time we didn't use the real bombs, but we can whenever we want to do so - nothing you've done can stop us."