Cello on or no cello at all, cigars that are kept in the right humidity consitions will be humidified right....
Found on a website, no need to rephrase:
"The cellophane wrappers on cigars are permeable, allowing oxygen to pass from the inside of your humidor to your cigars. Air and humidity will pass through the wrapper membrane, albeit slowly, since the cello is permeable but not porous. In any case, you needn't worry about the ability of individual cigars to age properly if you keep the cello wrapper on, they will be able to "breathe."
If your cigars are in fact dry, they were either cery dry before you put them on in your humidor, of there is a problem with your hygrometers....
How's the seal on your humidor?