Well I kinka like  not having a lot of addresses on  the "To" line. It
makes the mail look better. Since  we are a backbone site having stuff
sent via DIST2 is a lot better  in terms of over all network load. The
fact that there  are a varity of  mailers on the network  can make any
attempt to  send single files  based on what mailer  is in use  a very
hard job. TCP/IP with SMTP adds more to the problem.
 
In our  area there are several  backbone servers which means  that the
number of messages distributed individually to other sites is reduced.
Any site which  has a large volume  of list mail may  wish to consider
installing a backbone server or have  a near by node become a backbone
server. It  really doesn't  take that  much effort  or disk  space and
would again cut down on network traffic.