Pity I'd invested after taking a short cut - such greediness! (8)
I believe the answer is:
cupidity
'cut such greediness' is the definition.
'cupidity' can be an answer for 'greediness' (I've seen this before). I am not sure about the 'cut such' bit.
'pity i'd invested after taking a short' is the wordplay.
'invested' is an insertion indicator.
'after' is a charade indicator (letters next to each other).
'taking a short' becomes 'cu' (I can't justify this - if you can you should believe this answer much more).
'pity' placed around 'id' is 'pidity'.
'pidity' put after 'cu' is 'CUPIDITY'.
Can you help me to learn more?
(Other definitions for cupidity that I've seen before include "Greed for gain" , "Greediness" , "Desire" , "Acquisitiveness" , "hunger for money" .)