Capricious duke uses dodgy flowchart to indicate his good fortune, maybe (4,2,3,4)
I believe the answer is:
luck of the draw
'capricious duke uses dodgy flowchart to indicate his good' is the definition.
I don't know anything about this answer so I can't judge whether this works.
'fortune maybe' is the wordplay.
I cannot really understand how this works, but
'fortune' could be 'luck' (synonyms) and 'luck' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for luck of the draw that I've seen before include "Result of complete chance" , "Chance, as in sweepstake" , "suggesting team should be thankful not to lose?" , "Sheer chance" , "Hazard of chance" .)