Only the large objects with oids (object identifier) from the dumped tables are dumped. That means that if a dumped table has an oid column and IncludeBlob=true, then all the oid values are verified for the existance of the corresponding large object, and these large objects are dumped. Don't forget that large objects oids should be stored in the oid type fields. Here is a simple DDL script that creates a table for storing oid references to the large objects.
CREATE TABLE test.largeobj_table ( loid oid )
Setting this property to true may significant increase size of the dump and make difficult its representation because of great amount of binary data.
Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2