I wouldn't get all in a huff about the voltage disparity. Many CREE circuits advertise a 10-30 volt input range. What I see is the upper 20% limit allows the circuit to get hotter which may not be tolerated too well in hot climates. Active voltage regulation is performed by switching which means electronic noise.
Simply adding a 3 amp axial diode to the 12+ supply wire will automatically drop voltage about .6 volt. This would mean a reduction from 14.0 to 13.4 volts. Heating reduction can be dramatic. Lifespan could be increased from a few hundred hours to decades lifespan.
I've made night lights out of bright LED lamps by using a diode on the + Side and a second on the - side.
