Pros / Cons of Database Backup Compression

SQL Server Administration
19

We use commvault to backup our SQL databases ... Commvault uses deduplication to reduce backup size :

http://documentation.commvault.com/commvault/v10/article?p=features/deduplication/c_deduplication_overview.htm

Commvault best practice section states "To improve the SQL backup performance with deduplication, ensure that the Native SQL backup compression option is 'OFF' on the Advanced Backup Options dialog box." :

http://documentation.commvault.com/commvault/v10/article?p=products/sql/best_practices.htm

I guess this is one possible situation where it is best to have compression disabled as a default.