Those forgetting which one escapes messianic complex (8)

I believe the answer is:

amnesics

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'those forgetting' is the definition.
I know nothing about this answer so I can't tell whether this works.

'one escapes messianic complex' is the wordplay.
'one' becomes 'i' (Roman numeral).
'escapes' is a deletion indicator.
'complex' indicates anagramming the letters.
'messianic' with 'i' taken away is 'messanic'.
'messanic' with letters rearranged gives 'AMNESICS'.

'which' is the link.

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I've seen this clue in the Sydney Morning Herald.

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