Has complete understanding, with hindsight? (5,9)
I believe the answer is:
'complete understanding with hindsight?' is the definition.
I don't know anything about this answer so I can't tell whether this works.
'has' is the wordplay.
I cannot really understand how this works, but
'has' could be 'knows' ('know' can be a synonym of 'have') and 'knows' is present in the answer.
The remaining letters 'backwards' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?