Interesting thought, Glenn, and one I didn't really think about. I did not have a tarp up either time, just open to the sky. I certainly had it closed up pretty tight (four inch or so breathing hole at the side down low--sleeping on stomach so nose/mouth very close to hole). Mentioned earlier that keeping down condensation took some practice/experimentation (on how much to open when) and in these cases it was just button up tight, so condensation is certainly possible (maybe inevitable) and "wetting out" is also likely. But the puddle was probably two or three cups of water in one case. Don't really think I could have collected that much condensation that fast, but lacking any other rational explanation, I certainly can't reject that one. Thanks.
Incidentally, I still liked that bivy a whole lot, used it the whole trail (six months), but in the end, just couldn't justify the weight when MLD item did such a good job for a fraction of the weight (Used the MLD bivy on second thru-hike). best,jcp