Google's Blogger software, by default, separates paragraphs by an "HTML break tag" (
br); this preserves the visible separation as intended, but destroys the structural, semantic flow. I recently discovered this, found the feature to turn it off ("don't put "break" tags in unless I bloody tell you to!), and set it. I naively thought that this would apply only to new posts, and posts that had previously been saved in the old, "broken", format would stay as is.
I must now go back and hand-edit every post over the last nearly five years so that their paragraph flow is properly marked up. Since I do in fact have other demands on my time, this is not likely to be completed immediately; it is, however, a very high priority.