I think that the main point is that all it does is allow the use of storage elements in the nested network, there's no crafting or exporting that can be done, it's not a full-featured system by any stretch of the imagination.
So, if you want, say, to have an MFR network to supply farm-like stuff, you need to have everything (fertiliser, bonemeal, etc.) available to that subnetwork, which would mean generating it there, or using channels, and giving that area of the network access to the place that everything else is stored.
It means that you can segregate networks, and it means that for the complex machines, you need channels, but if it's just a massive storage system, it's a fairly trivial matter.
So, if you want, say, to have an MFR network to supply farm-like stuff, you need to have everything (fertiliser, bonemeal, etc.) available to that subnetwork, which would mean generating it there, or using channels, and giving that area of the network access to the place that everything else is stored.
It means that you can segregate networks, and it means that for the complex machines, you need channels, but if it's just a massive storage system, it's a fairly trivial matter.