Well, obviously in the real world, devices do not have unbounded transmit rates. But you can get pretty damn close to the transmitter. The Shannon limit isn't t

Well, obviously in the real world, devices do not have unbounded transmit rates. But you can get pretty damn close to the transmitter. The Shannon limit isn't the only relevant limit, and is no reason to dismiss out of hand an entire class of optimizations that do help in the real world. (Also, even if your equipment is capable of hitting the Shannon limit, I'm not convinced that transmitting at the highest power level is going to be optimal for multi-party communications with geographically distributed APs and stations. The information channel between my neighbor's AP and his laptop is neither identical to nor completely separate from the information channel between my AP and my laptop.)