-dit(bf(-n, --dry-run)) This tells rsync to not do any file transfers,
-instead it will just report the actions it would have taken.
-
-dit(bf(-W, --whole-file)) With this option the incremental rsync algorithm
+dit(bf(-n, --dry-run)) This makes rsync perform a trial run that doesn't
+make any changes (and produces mostly the same output as a real run). It
+is most commonly used in combination with the bf(-v, --verbose) and/or
+bf(-i, --itemize-changes) options to see what an rsync command is going
+to do before one actually runs it.
+
+The output of bf(--itemize-changes) is supposed to be exactly the same on a
+dry run and a subsequent real run (barring intentional trickery and system
+call failures); if it isn't, that's a bug. Other output is the same to the
+extent practical, but may differ in some areas. Notably, a dry run does not
+send the actual data for file transfers, so bf(--progress) has no effect,
+the "bytes sent", "bytes received", "literal data", and "matched data"
+statistics are too small, and the "speedup" value is equivalent to a run
+where no file transfers are needed.
+
+dit(bf(-W, --whole-file)) With this option the delta-transfer algorithm