Cryptic crossword clue
Naively optimistic, continued drinking whiskey next to Romeo 6-4

The most common and most likely answer to this crossword clue is the 6 plus 4 letter word STARRY EYED

I've seen this crossword clue in The Daily Telegraph
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Buddy explains!

The straight part
We know that "Naively optimistic" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case naively optimistic = starry eyed.
The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.
This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.

What does STARRY EYED mean?

STARRY EYED adjective
  1. Having naively optimistic hopes or outlooks.

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