finetjul/Slicer — comment on commit b76e3b1fe2add2f08d339ab2c7ab7a5ed3cf79a8
File: Libs/MRML/vtkMRMLScene.h line 371
By jcfr:

Observers can ignore the events \a NodeAddedEvent or \a NodeRemovedEvent when the scene is in \a BatchProcessState to just synchronize with the scene when \a EndBatchProcessEvent is fired.