I have mentioned Nikolajava and Scott's How Picturebooks Work before and do urge you to read around the wider critical debate they provide. They write, ‘If words and images fill each other's pages wholly, there is nothing left for the reader's imagination, and the reader [child read to] remains somewhat passive’ (2006: 17). This is exactly what I was saying above when I suggested that a picture book was a participatory piece of art which encourages engagement. And in thinking about the passivity problem they add,
The same is true if the gaps are identical in words and images (or if there are no gaps at all). In the first case, we are dealing with the category named ‘complementary,’ in the second, ‘symmetrical.’ ...