Most graceful Soviet letters regularly focus with Putin (8)

I believe the answer is:

sveltest

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'letters regularly focus with putin' is the definition.
I can't judge whether this definition defines the answer.

'most graceful soviet' is the wordplay.
'most' means to remove the last letter.
'graceful' becomes 'svelte' (similar in meaning).
'soviet' becomes 'est' (I can't explain this - if you can you should give a lot more credence to this answer).
'svelte' with its final letter taken off is 'svelt'.
'svelt'+'est'='SVELTEST'

Can you help me to learn more?

I've seen this clue in The Guardian.

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