Fussy bar being disconnected from net? (4-9)
I believe the answer is:
hair-splitting
'fussy' is the definition.
'bar being disconnected from net?' is the wordplay.
I cannot really see how this works, but
'from' could be 'in' (I've seen this in other clues) and 'in' is found in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for hair-splitting that I've seen before include "Pedantry" , "Making of petty distinctions" , "Occupied with petty distinctions" , "Making trivial distinctions" .)