Strictly requires this old couple to visit branch (8)
I believe the answer is:
footwork
'strictly requires this' is the definition.
The definition suggests a singular noun which matches the answer.
'old couple to visit branch' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'couple' becomes 'two' (I've seen this before).
'to visit' is an insertion indicator.
'branch' becomes 'fork' ('fork' can be a synonym of 'branch'**).
'o'+'two'='otwo'
'otwo' inserted within 'fork' is 'FOOTWORK'.
Can you help me to learn more?
(Another definition for footwork that I've seen is " Skilful manoeuvring".)