Argued about the high speed, indeed! (7)

I believe the answer is:

debated

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'argued' is the definition.
('debate' can be a synonym of 'argue')

I cannot understand how the rest of the clue works.

(Other definitions for debated that I've seen before include "Shared opinions" , "Discussed in public" , "Argued" , "Contemplated" , "Considered" .)

I've seen this clue in the Evening Standard.

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