Lead developers vs 'Helpers'

I got to thinking...

From a free software business point of view, what is the difference
between 'lead developers' and 'helpers'.

With many medium sized projects, it's pretty obvious who runs things
and does most of the work.  This is the person who you would also go
to for consulting, training, or whose name would look best on a book,
even if there are other people who know the code and do work on it.

I wonder how important this distinction is in economic terms?

-- 
David N. Welton
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