Key skill of one cutting power and mains supply (7)
I believe the answer is:
pianism
'key skill' is the definition.
'pianism' can be an answer for 'skill' (I have seen 'Musical skill' mean 'pianism' so perhaps 'skill' could also mean 'pianism'). I'm not sure about the 'key' bit.
'one cutting power and mains supply' is the wordplay.
'one' becomes 'i' (Roman numeral).
'cutting' indicates putting letters inside (some letters cut their way into a word).
'power' becomes 'p' (symbol in physics).
'and' says to put letters next to each other.
'supply' indicates anagramming the letters (in a supple way).
'p'+'mains'='pmains'
'pmains' is an anagram of 'panism'.
'i' placed into 'panism' is 'PIANISM'.
'of' acts as a link.
Can you help me to learn more?
(Another definition for pianism that I've seen is " Musical skill".)