A bad rule can be surprisingly long-lasting (7)

I believe the answer is:

durable

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'surprisingly long-lasting' is the definition.
'durable' can be an answer for 'long-lasting' (synonyms). I am not sure about the 'surprisingly' bit.

'a bad rule can be' is the wordplay.
'can be' indicates anagramming the letters.
'bad'+'rule'='badrule'
'badrule' with letters rearranged gives 'DURABLE'.

Can you help me to learn more?

(Other definitions for durable that I've seen before include "Lasting a long time" , "Firm" , "Capable of lasting" , "Likely to last" , "Hardy" .)

I've seen this clue in The Irish Independent.

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