brtools + RMAN versus RMAN only

Hi, ALL

I have read some white paper regarding brtools+RMAN versus RMAN,

it says: "'brtools+RMAN' is better than 'RMAN only' since brtools does not require recovery catalog",

From what I know of, RMAN has "nocatalog" option too, also, to have a catalog database seems safer than nocatalog,

So what is the advantage to use brtools+RMAN over RMAN only?

RMAN has command to control the backups, for example, delete certain backup, does brtools also have such function?