I'm not sure what the significant complexity is, but I wonder if it has to do with EIS (Electrochemical Impedance Spectroscopy). From the way I understand it, this is what Berman was referring to when he said they have already perfected the technology because they were already using it in the TBG GenUltimate blood glucose device.

Like I've said before, in my understanding, the GenViro Saliva, GenViro Blood and the TBG GenUltimate are all related through EIS technology, so maybe that's where complexity lies.