> How is the reverse any better?
> 
> If you don't download the sources for the requested package first, you
> could spend time building all the dependant packages, only to find out
> that the one you actually wanted is broken/unavailable.

how likely is it that the source is unavailable, while all the packackes'
sources it depends on are available?

> Since the build time in this case will almost always exceed the download
> time in the current setup, the current setup seems better to me.

it depends what is more "costly" to you: building time or download
volume/space. If the latter does not matter, I agree that the current
scheme fits best. If it does however, the other approach would make more
sense.

-- 
Georg Schwarz    http://home.pages.de/~schwarz/
 geos@epost.de     +49 177 8811442