just to add to the curing part, if 1 section cures faster, that prevents another section from pushing out resin as it cures; thus increasing the density in the slower curing section. Or the faster curing section is pushing its excess into another section that is not vented, also increasing density. Hmmm, sounds legit for why the sections are inconsistent.
dang-it, that means I have to make a silicon mess again... not my favorite part of lure making. oh well, thanks for the info nitro98! my confidence has been boosted!