TDMA CC system = good salespeople.
There are quite a number of agencies already on P25 trunking that can benefit from TDMA control channels. Think about the small system that only has 2 frequencies licensed, they gain an additional voice slot and go from either 2 to 3 if already TDMA, or 1 to 3 if currently FDMA. That is not insignificant. Also consider the really large simulcast cells that need more capacity. By using both slots of the control channel for signaling, it allows them to nearly double the amount of repeaters in the cell. Current FDMA control channels limit the amount of traffic channels at a site because they can only push through so much signaling per second, and so TDMA signaling makes an appreciable difference.
Don't be too quick to poo poo the whole idea of TDMA control channels being smoke and mirrors or nothing more than a way for salespeople to line their pockets. It's very easy to be cynical when it comes to this sort of stuff, but there is real value in these advancements. Especially when DMR already offers TDMA control channels. You can argue about P25 being way too pricey to begin with, especially as compared to DMR...but that ship sailed decades ago. The reality is that there are a ton of agencies on P25 trunking, and for some of them, these sorts of advancements are important to them.
Oh and LTE replacing LMR is a very long way off. It's simply not ready for prime time. Anyone who has used FirstNet knows that it's not all it's cracked up to be. Besides, who the hell really wants to put all of their eggs in one basket that they have absolutely no control over, and is controlled by a for-profit corporation vs the agency or county or state government? No thanks!
