How obscure coteries all stray, ultimately? (12)

I believe the answer is:

esoterically

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'how' is the definition.
Both the definition and answer are adverbs.
Perhaps there's a link between them I don't understand?

'obscure coteries all stray ultimately?' is the wordplay.
'obscure' indicates an anagram.
'ultimately?' indicates one should take the final letters (I've seen 'ultimately' mean this).
The last letter of 'stray' is 'y'.
'coteries' with letters rearranged gives 'esoteric'.
'esoteric'+'all'+'y'='ESOTERICALLY'

Can you help me to learn more?

(Another definition for esoterically that I've seen is " in a mysterious way".)

I've seen this clue in The Times.

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