4G on the Evo (Sprint) is different than 4G on the Thunderbolt (Verizon). But as far as I know, voice over LTE has not been enabled. The ability to use voice and data at the same time with the Thunderbolt is on 3G right now, but I believe it uses a different type of 3G radio than the norm to make this happen.
Ok, let's clarify this.
The TBolt uses CDMA for voice and 3G Data. Voice and Data are only guaranteed to work in 4G coverage areas.
The reason? 3G CDMA and 4G LTE are two different technologies with different radios.
You are right that 4G only supports data which is why you can be on a CDMA (dates back past 1X) voice call and still use LTE data.
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