We redirected because of language/national organization subsite tracking issues, all done by our custom version of rp_filter. We could've worked around this given more time but time was something we didn't have much of.
And in addition we're using the host-node map to "deep link" into the site, as GP traditionally offers domain names for various issues. In our case this mean mapping to a node within the site along with a query string - and there's no easy way to append the query string to the structure built by AOLserver that's then returned by ns_form (I looked :)
Redirecting solves that problem ... now we can map any domain to any arbitrary page + query string in the site.
So given that we couldn't cheaply avoid redirection in all cases and had little time to even fiddle with the simpler case, we just punted and redirected in all cases.
