I have seen some answers which are correct in the concept required by the question asked by OP, but which lack some explanation. Now, if the OP is quite acquainted with the concept which his question is concerned with, he just might need a step to find the required answer. In that case, the answers having minimal description are acceptable.
However, I feel there might be users who need an explanation as to where certain terms in the answer came from, those who have recently been introduced to those concepts. This happens mostly in problems of combinatorics.
What I wanna ask is
Is it good manners to elaborate someone's answer, keeping the same approach?
Edit: I did something of the sort in here. Is that acceptable? By elaborate, I mean write a new answer, keeping the same approach, but explaining the steps in detail. No touching the answer of someone else!