Exchange DAG replication using secondary NIC betwene servers on different subnets

Recently I ran into a problem with Exchange 2010 DAG configuration. I needed to replicate databases between servers that were geographically in different sites and were each on their own separate subnets. For this purpose I wanted to use our secondary data line in order to avoid overloading our main production line with replication traffic. DAG was all set and replicating fine over production line but when I disabled replication on main NIC's and enabled it on secondary NIC's routed via secondary data line, Exchange was still pushing replication via primary NIC. Issue resolved after I collapsed DAG network on secondary ISP into a single DAG network adding both near and far subnet into it. Great article that talks just about that particular setup you can find right here: http://blogs.technet.com/b/timmcmic/archive/2011/09/26/exchange-2010-collapsing-dag-networks.aspx