The RAF hero sat reviewing his deepest feelings (5,2,6)

I believe the answer is:

heart of hearts

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'his deepest feelings' is the definition.
I don't know anything about this answer so I cannot tell whether this works.

'the raf hero sat reviewing' is the wordplay.
'reviewing' indicates anagramming the letters (To re view).
'the'+'raf'+'hero'+'sat'='therafherosat'
'therafherosat' is an anagram of 'HEART OF HEARTS'.

Can you help me to learn more?

(Another definition for heart of hearts that I've seen is " Inmost convictions".)

I've seen this clue in The Irish Times.

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