VoLTE (Voice over LTE) is finally becoming a reality, with the pace of commercial deployments quickening and the big two US carriers enlarging on their grand plans. However, the technology remains a defensive move. Most operators cannot quite let go of their traditional voice/messaging cash cow altogether, and are looking to VoLTE, as part of a broader set of unified communications services, to differentiate themselves from Skype and keep cellco voice relevant. However, because it requires wide area coverage, and is reliant on a hefty IMS (IP Multimedia Subsystem) deployment, VoLTE is a big ticket item on the carrier’s spending plan. And it is tough to see how that investment will be justified except in the defensive sense of slowing…