Achievable: Drastic drop in bad cell phone connections. Massive MIMO - 64 or more antennas - can dramatically improve edge performance by "beam forming," directing the signal where the users are. Done well, it can dramatically improve the performance where it's weaker. Hidebumi Kitahara of Softbank told me that is working very well and will get better as software improves. See "I am crazy about Massive MIMO," Kitihara of Softbank ordering 1,000's of Massive MIMO bases
Robert Clark of Light Reading reports Kitahara intends to use the capacity to improve performance for all users. "We don't care about peak throughput. We want to minimize the low throughput, which is between 1 Mbit/s and 5 Mbit/s." Clark adds, "At those speeds, the network will struggle to deliver a good video experience. Prior to deployment, around 20% of all users were experiencing throughput below 2 Mbit/s." Kitahara reveals, "only a few percent," now receive low speeds.
The massive MIMO solution, using 128 transmitters, ensured that users were getting at least 5 Mbit/s data throughput. Kitahara had already installed 100 base stations last November and ordered thousands more.
Both Peiying Zhu of Huawei and Professor Erik Larsson make that point in these short videos.