Thick report overly impatient with approach to knots not loosened? (3,5,6)

'knots not loosened?' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'thick report overly impatient with approach to' is the wordplay.
I cannot really understand how this works, but
'impatient' could be 'short' (similar in meaning) and 'short' is found within the answer.
'with' could be 'w' (abbreviation) and 'w' is located in the answer.
'approach' could be 'plan' (I've seen this in another clue) and 'plan' is present in the answer.
'to' is found in the answer.
This explanation may well be incorrect...

Can you help me to learn more?