So from a practical standpoint they were well briefed on what to expect, thought that's not to say they weren't still surprised awed by witnessing the detonation and blast. Not to mention the support aircraft that flew along to make measurements and observations as well.
From a practical standpoint they were pretty well versed b/c the payload required very specific and distinct handling such as loading over special pits dug into the ground, arming the bombs during the flights, taking into account how much flight characteristic would change at the moment of dropping the bomb (by instantaneously shedding a significant proportion of the plane's grosse weight) and by receiving instructions for the path to be taken in the immediate aftermath to avoid the blast and confirm / observe detonation.
