After reading that, it seems like it is going to be a low-throughput network. There's only so much space you can occupy with a signal between those band marker

After reading that, it seems like it is going to be a low-throughput network. There's only so much space you can occupy with a signal between those band markers without conflicting with other spectrum users. Even if you multiplexed a couple conventional signals you'll still wind up below EDGE-type throughput.