I'm Oracle University Instructor and each time I read in the Slides about RMAN : "configure autobackup controlfile ON -> Oracle Strongle Recommend it", I ask myself why is OFF by default?
In my opinion should be ON by DEFAULT, and I though the problem could be purging autobackups. So,it could have a purge policy by default.
Example :
CONFIGURE CONTROLFILE AUTOBACKUP ON;
CONFIGURE RETENTION POLICY AUTOBACKUP CONTROLFILE TO REDUNDANCY 3;
I think to purge you could use the same algorithm that is used in RAC to purge automatic backups of OCR.
Using for purging the pathname default that exists in autobackup format.
CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '%F';