Note that if it doesn't find a DESTROY method for an object, perl doesn't mind; perl only calls DESTROY if it appears to exist. And if you have an AUTOLOAD method, perl (intentionally) will find that when looking for a DESTROY.

(For what it's worth, the import and unimport methods implicitly called by use and no don't work this way; if they don't exist but AUTOLOAD does, AUTOLOAD isn't called.)