YMMV, depends on if it registers to the network or not. Verizon REQUIRES a phone's IMEI\ESN to be registered in their system for the CDMA functionality to work. If it's a verizon branded iPhone, by putting in the SIM it enables the LTE and CDMA because the two are already on file so it's an automatic process. In most cases, if you just slip a SIM into a sim-free iPhone, it'll work fine on LTE, however there will be issues with the CDMA side of it until you call Verizon and associate the IMEI\ESN to the network manually. Since most people never leave LTE on verizon these days most wouldn't even notice most likely.
But sorry, you lost a bit of credibility calling objective lab tests "anecdotal evidence" .... the very definition of anecdotal is "not necessarily true or reliable, because based on personal accounts rather than facts or research." The very facts that brought this entire Intel vs Qualcomm debate to life were based on fact and evidence obtained by research. Maybe less time trying to make joke and more time on actual facts.