In Org, entry text can't have substructure (other than drawers and plain lists): you can't have an entry that has some text, then a subtree, then more text. I just (re-)discovered that you can get around that by using "#+BEGIN_SRC org" to include arbitrary org subtrees in the middle of entry text. That's useful not just when writing in Org about Org, but anytime you want to insert an extended sidenote in the middle of an entry. As with all source blocks, you edit it in its native (Org) mode and it exports correctly. You can copy links from the main Org and past them into the nested Org.
Just wish I'd learned this sooner :) So, maybe mention this in the manual in the sections on drawers and plainlists. ilya
