Hi,
on the document you linjed, page 5, it talks about incremental backups. I quote (page 5)
BRBACKUP supports incremental backups of the database with RMAN. The Oracle Recovery Manager offers two types of incremental backup: cumulative and differential. The integration of RMAN into BRBACKUP is restricted to cumulative incremental backups at level 1.
sooo,
what was the question, again?