How to use "or" and the adverb "as"?

I There is no obligation to repeat "as"; the examples shown in Google Books make that clear. The page from which the information has been extracted is "Google search-whether as a". However, "as" is more often repeated. There is no evident rule that could be inferred from the examples to tell when this preposition can be omitted.

as-1 Accordingly, anyone involved in the management of public gardens, whether as a director or area supervisor, and irrespective of the type and size of such facility, would have to have familiarity with various aspects of garden organization and

as-2 Once in psychoanalysis, whether as a practitioner, a patient or a theoretician, one is not in hospital anymore, indeed, not in medicine any more – not in any of these medically integrated roles.

as-3 APO as supply chain DSS; product from company competing with SAP as supply chain transactional ERP From the point of view of any educational treatment of APO, whether as a classroom delivery or textual reference, the first case is the

as-4 at a factory or in an office downtown or in a private studio. Your place or type of work doesn't matter to God. What does matter to Him is being in His will (Romans 12:2). You should approach your vocation, whether as a painter or a plumber, ...

as-5 an elector for having voted or refrained from voting; (B) the receipt of, or agreement to receive, any gratification, whether as a motive or a reward—

as-6 whether as a lost theater ticket or a lost bank note in the same value; whether as a gain or a loss, depending on how you describe the baseline; whether as being an issue of fairness or ordinary market behavior

as-7 When a person enters a culture, whether as a child or an outsider, we are confronted by a context that is “overexplained, overdetermined by meaning”

as-8 So that now , as regards the parties to an action , it is essential well to ascertain the right to join , as well as the expediency and propriety of joining a person , whether as a plaintiff or a defendant, before the commencement of such action ;

as-10 To be a citizen is to be designated as someone who can participate in these kinds of mechanisms, whether as a voter or a representative or both.

as-11 An Obliging man, whether as a master or a servant, is one of the greatest ornaments to human society.

as-12 Schools of thought differ also in how they view the organization of the human being, whether as a kind of biological organization, a kind of psychological organization or a kind of imported societal organization incorporated from the social

II In addition to the cases "1" and "3" which show the omission of the determiner "a" there are two more below that can be found in the same source. The determiner "a" is rarely omitted. it seems that at least in some syntactic contexts there is also the possibility to omit the determiner "a".

a-1 That power lies in the link from portrait to subject whether as a world leader or seemingly unknown but loved individual.

a-2 as an historical source, whether as a witness to the events it describes or as witness to its own values and ideas.