Strengthening control for hard stuff (13)

I believe the answer is:

reinforcement

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'strengthening' is the definition.
(I've seen this before)

'control for hard stuff' is the wordplay.
'control' becomes 'rein' (reining is a kind of controlling).
'hard stuff' becomes 'cement' (cement is a kind of stuff. I am not sure about the 'hard' bit.).
'rein'+'for'+'cement'='REINFORCEMENT'

Can you help me to learn more?

(Other definitions for reinforcement that I've seen before include "More support needed" , "supporting structure" , "additional support" , "Back-up" , "Strengthening" .)

I've seen this clue in The Times.

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