I didn't claim it did. But you get diminishing returns from around 1bit/s/Hz if you just turn up the power. Your energy efficiency will go down, a lot. The mor

I didn't claim it did. But you get diminishing returns from around 1bit/s/Hz if you just turn up the power. Your energy efficiency will go down, a lot. The more you can get spatial multiplexing to keep you away from that border, the less energy you'd need to dump into the air. And as computing get's cheaper, that energy tradeoff moves more and more towards MIMO. Back in 2005 we didn't have a need to think of 8x8 MIMO (Laptop <=> AP). Now it becomes realistic, so we got it specified and standardized in 802.11ac to allow everyone to join in the testing/experimental setups.