I noticed something like this, too, on a different flavor... please bear with me, skipping to something that appears unrelated
I clean my upper dentures, when removed, with a sonic toothbrush first before doing other cleaning to them... The other day I noticed a sticky patch after using the sonic toothbrush. I scratched with my fingernail and found a semi-thick coating. I, then, scratched areas that appeared clean and found the same coating. In essence, this coating was not really visible, was not removable with the sonic toothbrush, and covered the outside/biting side of the denture.
Considering this, I think it is possible that as we vape this same sticky coating occurs with our taste buds and that this cloaks the taste of the ejuice.
When I started
vaping regularly, I got the morning-after sore throat, and got rid of it by gargling with Coca-Cola right be for bed. (I got the idea from reading the atomizer cleaning thread).
Thus, I think that perhaps our brushing, flossing, and regular gargle might not be completely cleaning our pallets... that we might benefit from something like a Coca-Cola gargle prior to regular cleaning methods and that this would also restore our pallets to full tasting.