Leadership : Positional or Functional

I thought we had slayed this beast but it seems there's still quite a lot of thinking on leadership around that sees it more positionally than functionally i.e. it's a position you hold rather than a function you carry out. Of course even those who see leadership positionally acknowledge that there is a certain functionality to leadership but would see it as flowing out of a place of position i.e. you do what you do out of the place you have been given.
I just can't buy into this. we must see leaders as those in the community of faith who have certain functions (which they do on behalf of the community) rather than people who have a certain status e.g. a priestly class.
I guess if there is a positional side to leadership it is one of being the last and the least - that's the position : servant of all.
As I'm writing this i'm wondering how it connects with a view of Ephesians 4 where it is the people themselves (i.e. apostles, prophets, evangelists, pastors, teachers) who are the gifts to the church rather than what they do per se. But i don't think Paul is talking about different kinds of leaders there (read the text - he's writing to the whole church and he says "to each of us grace has been given....some to be apostles etc.) so perhaps that's the answer.
what we do certainly flows out of who we are but those of us who are leaders in the church must never see who we are in a positional sense of status.