Extreme crossword solvers had side-bet, about classic revenge? (1,4,4,6,4)

I believe the answer is:

a dish best served cold

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'extreme crossword solvers had side-bet about classic revenge?' is the definition.
I know nothing about this answer so I can't tell whether this works.

'extreme crossword solvers had side-bet about' is the wordplay.
'extreme' says to hollow out the word (remove centre letters).
'about' indicates anagramming the letters.
'crossword' with its middle taken out is 'cd'.
'cd'+'solvers'+'had'+'side'+'bet'='cdsolvershadsidebet'
'cdsolvershadsidebet' with letters rearranged gives 'A DISH BEST SERVED COLD'.

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

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