[net.arch] Why is everything cross-posted?

dww@stl.UUCP (David Wright) (12/18/85)

Does anyone know the right bit of 'magic' to put in my (rn) KILL file for
net.micro to eliminate anything which has been cross-posted to net.arch?
At present I'm tempted to un-subscribe to net.micro 'cos all the good stuff 
is in net.arch anyway.