Very flexible person American's greeting with grunt (4)

I believe the answer is:

yogi

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'very flexible person american's greeting with grunt' is the definition.
I can't tell whether this defines the answer.

'greeting with grunt' is the wordplay.
'greeting' becomes 'yo'.
'with' is a charade indicator (letters next to each other).
'grunt' becomes 'gi' (both can mean a US soldier).
'yo'+'gi'='YOGI'

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(Other definitions for yogi that I've seen before include "stretcher found?" , "Master of a Hindu philosophical system" , "master of posturing?" , "practitioner holding various positions" , "Spiritualist" .)

I've seen this clue in The Independent.

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