Once more check and control cult holding power (9)

I believe the answer is:
reinspect
'once more check' is the definition.
The definition suggests a verb in its base form which matches the answer.
'control cult holding power' is the wordplay.
'control' becomes 'rein' (reining is a kind of controlling).
'cult' becomes 'sect' (religious sect).
'holding' is an insertion indicator.
'power' becomes 'p' (symbol in physics).
'sect' going around 'p' is 'spect'.
'rein'+'spect'='REINSPECT'
'and' is the link.
Can you help me to learn more?
(Other definitions for reinspect that I've seen before include "Further check" , "Do follow-up work for Ofsted" .)
