Unedifying attitude that may set teeth on edge (4,6)

I believe the answer is:

sour grapes

I believe this clue is a double definition.

'unedifying attitude' is the first definition.

'that may set teeth on edge' is the second definition.

(Other definitions for sour grapes that I've seen before include "Disparagement of something one wants but cannot attain" , "Sham disdain for what one cannot have" , "Jealous resentment" , "pretended disdain" , "with a bitter aftertaste?" .)

I've seen this clue in The Guardian.

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