The reason that they avoided it was it would take an additional antenna installed - no more - no less. The Qualcomm chipset supports it. For most of the areas around here, you can't do it with AT&T anyway (you don't get HSPA+ - only Edge). For a "dying" technology it sure is still holding strong. In some aspects CDMA is better than GSM. Also, you ARE aware that 3G GSM IS actually a type of CDMA aren't you? Furthermore, there is NO reason in an LTE market that the phone should not be capable of doing dual voice/data as can the other Qualcomm chipset equipped phones that are on the market. As far as I know, ALL the recent LTE phones provided by Verizon WILL do voice/data at the same time on an LTE network (which is getting to be pretty widespread - heck, even in this tiny town we are about 70% covered by LTE and they already have the pads in build for new towers to make it 100%).
The funny thing is - even on AT&T's towers, if you do the voice/data routine while on LTE you LOSE your LTE speeds for that period. With the Verizon CDMA/LTE combo you maintain those data speeds.
You want to really know the ins/outs of the reason it won't support it a couple of good articles are located
here and
here.