I'm looking at similar stuff right now.  I set up a local
test and found an explanation.  Seems the final statistics
aren't right, but the log has it.  The transfer-status line
has 'link updated' for files that changed on the server,
'link recorded' for files that were taken from the cache,
'link added' for files that weren't in the cache, and 'link
error' for others (e.g. files that are gone -- not sure if
we can tell that they were in the cache).

-Lars