RMAN Backups

We are using RMAN to perform daily, full database backups. This includes all datafiles, password file, init file, control file and archived log files. The database is running in archivelog mode. We were testing recovery of the database by deleting index datafiles and then attempting to restore using RMAN. Everything seemed to work well until we started using the indexes. There were numerous block corruption errors reported after the restore. Prior to the restore, there were no block corruptions and after a restore from a cold backup there were no block corruptions. It appears that RMAN caused this. We're seeing ORA-01578, ORA-01110, and ORA-26040. Has anyone else seen anything like this? I'm questioning whether or not I should be using/trusting RMAN for backups. Any insight would be appreciated.

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