Turns out you can add my blog's RSS feed to your LJ friends list even without a paid account. Just go here:
And add that fake user as a friend. Keen! (Just don't use LJ's commenting system to discuss those posts -- use the commenting system on my site, otherwise I probably won't notice your comments. Of course since within LJ you only see a short snippet of the posts, hopefully no one would think to comment there anyway...)
And on the subject of keen features of LJ, I discovered that I can easily fix both of my big complaints about the layout of the aggregated friends page, merely by customizing the layout it uses. Yay for customizability. So now I can see who a post is written by at the top of the post (instead of it being vertically centered and hence off the page when looking at a long post), and also posts are neatly separated rather than blending into each other when people don't include a title for their entries. Huzzah!