Oh, it's very clear which are flashbacks and which are now. The flashbacks are set off sections, italicized. The italics make them more annoying to read and, while they may or may not contribute to the ending of the story, they don't seem to matter much to the story in THIS book. I mean - the contents, summarized in a sentence or two (for all the flashbacks)? Yes, those matter. The whole of them? Not in the least.
no subject