Side with weak ruler? Innovative approach to solving problem (7,8)

I believe the answer is:

lateral thinking

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'innovative approach to solving problem' is the definition.
(thinking in an unusual way)

'side with weak ruler?' is the wordplay.
'side with' becomes 'lateral' (synonyms. I am not sure about the 'with' bit.).
'weak' becomes 'thin' (similar in meaning).
'ruler?' becomes 'king' (king is a kind of ruler).
'lateral'+'thin'+'king'='LATERAL THINKING'

Can you help me to learn more?

(Other definitions for lateral thinking that I've seen before include "unconventional views" , "Intuitive reason" , "Creative activity" , "Problem-solving technique" , "Problem solving using an indirect approach" .)

I've seen this clue in The Telegraph.

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