Sinnhaftigkeit von authentifizierenden block chiffre modi ohne Schlüssel

[Kas Ob.]

Will work, but if you are going to warn about wrong doing/using then make sure to put the warning about using the same key.

Same key only can be reused in different operations if and only if IV is different, that goes for GCM and CCM, (well it goes for anything to do with AES or any block cipher for that matter).
In other words: if no IV is used, then key must be different and not used more than once, if the key is same then IV must be different each time.