Saw is, after all, not quite cutting grass (8)
I believe the answer is:
realised
'saw' is the definition.
Both the definition and answer are past participle verbs.
Perhaps you can see an association between them that I don't see?
'is after all not quite cutting grass' is the wordplay.
'after' says to put letters next to each other.
'not quite' means to remove the last letter.
'cutting' is an insertion indicator (some letters cut their way into a word).
'grass' becomes 'reed' (I've seen this before).
'all' with its final letter taken off is 'al'.
'is' put after 'al' is 'alis'.
'alis' placed within 'reed' is 'REALISED'.
Can you help me to learn more?
(Other definitions for realised that I've seen before include "Achieved; red aisle (anag.)" , "Became aware of in sidereal way" , "Came to understand" , "Understood - cashed in" , "Came to know" .)