After a "block quote" section, line spacing is reduced. This was a bug with this template long, long ago, but was allegedly fixed (in the "classic" version) way back when.We'll see if it's still a problem. Maybe it's just a bug that affects posts that were made using the "classic" template. If it's an ongoing problem, I expect I will need to be re-upgrading my template sometime!
UPDATE: Fixed it! It took some digging and link-following, but other people have encountered this problem before me and have worked out some elegant (and some not-so-elegant) solutions. But it should've been right from the start. This is an issue that was identified a long time ago.
Here are the relevant links:
From Blogger Help Group
From The REAL Blogger Status