Let the creation protocol take as argument a possible content, and let executing it simply be using that argument as the new certificate's content. The "reconsideration" procedure would take an optional argument; if the optional argument is not supplied, then leave the object intact, otherwise update the content to the specified argument.
Of course, if we were to do this assimilation to a single kind of object, we should drop the terminology of "certificate" in our general exposition, and simply say each object kind has creation and reconsideration procedures. The fact that simple reconsideration of our "degenerate" kind of object leaves its instances intact means that their being marked for reconsideration would have no effect.
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