Really miff founders swallowing 2000 deception (12)

I believe the answer is:

flimflammery

I'm a little stuck... Click here to teach me more about this clue!

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

'really miff founders swallowing 2000' is the wordplay.
I cannot really see how this works, but
'2000' could be 'mm' (2000 in Roman numerals) and 'mm' is present in the answer.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?

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

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