Heating oil the centre of interest in striking success (4)

'heating oil' is the definition.
I don't know anything about this answer so I cannot tell whether this works.

'centre of interest in striking success' is the wordplay.
'centre of' indicates the central letters.
'in' is an insertion indicator.
'striking success' becomes 'ko' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
The middle of 'interest' is 'er'.
'er' placed within 'ko' is 'KERO'.

'the' acts as a link.

Can you help me to learn more?