Person that addresses tips to improve one's work (8)
I believe the answer is:
oratorio
'work' is the definition.
(I've seen this before)
'person that addresses tips to improve one's' is the wordplay.
I cannot quite see how this works, but
'person' could be 'orator' (orator is a kind of person) and 'orator' is present in the answer.
'one' could be 'i' (Roman numeral) and 'i' is found within the answer.
A single letter 'o' remains which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for oratorio that I've seen before include "Musical work for orchestra and voices" , "Musical composition for voices and orchestra based on a religious text" , "Sacred, dramatic music" , "Musical composition usually with biblical theme (8)" , "Work for voices, chorus and orchestra with biblical theme" .)