However, AT&T LTE is not really fast enough to take advantage of this feature, because a single 802.11g/n band is enough for LTE's speed

The 5ghz isn't used all of the time as many laptops only support the 2.4ghz band, but if you've ever found yourself in a crowdded conference with everyone else trying to use wifi, having devices that can work on the less crowded 5ghz band is advantageous

There is a G class (2.5ghz) secondary band available as well, so you can even link up to devices farther away, or connect to older B/G Wifi printers, etc.

Inside is a recent Qualcomm chipset that supports all the LTE bands as well as dual-band WiFi over 5GHz 802.11n ("2x2 MIMO")

works as it should do