Yes, an
individual revision can be deleted. There are at least three
different ways to do this, last I checked. I would expect that the
old ways (oversight, and delete+selective undelete) would leave no
traces at all in the dump, while the new way (rev_deleted) might only
suppress certain fields. I'm not sure offhand, though.
IIRC, any revision that has any of the rev_deleted bitfields set will be
excluded from dumps. Don't quote me on that....
--HM
They will appear with a deleted="deleted" attribute, so the content of
the suppressed fields isn't available, but that of the other fields is.