(*An) astute businessman though he was, P was capable of extreme recklessness
(*The) actual perpetrators though they were, the criminals never admitted their guilt in court
Why are the articles not allowed in this structure?
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Sign up to join this community(*An) astute businessman though he was, P was capable of extreme recklessness
(*The) actual perpetrators though they were, the criminals never admitted their guilt in court
Why are the articles not allowed in this structure?
It appears to me the examples you have presented are cases of the 'zero article'.
If the noun is countable and plural (e.g.., "research studies") or uncountable (e.g., "information") and it is being used in a nonspecific or generic way, no article is used.
Here are some more specifics:
No article is used when a plural countable noun is generic or nonspecific.
{Notice that an article does not appear before 'pens', 'pencils', 'Cats' or 'Babies'.}
No article is used when a noncount noun is generic or nonspecific.
{Notice that an article does not appear before 'milk', 'rice', 'homework' or 'research'.
[Reference: Walden University]
I hope this helps.