Dungeon Master of Middle-earth
Um no, just enough sight lines to the thing an observer is trying to see to make it so it can't be seen (clearly).But we know that foliage dense enough provide Heavy Obscurement gives effectively gives observers the Blinded condition when trying to see anything in the area. The only way that can be true is if every possible sight line is obstructed by foliage.
I'm looking out across my backyard, and not more than forty feet away is a clump of trees with large leaves covering its branches which trail to the ground. A person could be standing in the shade among those trees right now. I can't tell, but I have no doubt that if there were such a person, they could see my house just fine by peeking through the small gaps in the leaves in front of them.So yes, in three dimensions the foliage isn't a "solid block of plant material". But when seen from a distance as a two-dimensional image, the overlapping opaque branches, stems, and leaves fill the entire area. If there were any significant gaps that persisted even 5' into the dense foliage an observer would be able to see a creature at the edge of the dense foliage, which Heavy Obscurement does not permit.
Yes, going back to the trees behind my house, even though the leaves and branches are close together enough in many places to obscure the presence of a person among the cluster of trees, there are also gaps large enough that I can see the shape and color of the house behind quite clearly.It sounds like you envision dense foliage as much less dense than I think the rules require. Even going with your interpretation, however, how can an area of dense foliage be sufficiently opaque to provide Heavy Obscurement to the creatures inside it while simultaneously not sufficiently opaque to provide Heavy Obscurement to creatures beyond it? (That is your position, yes? That a creature/object among the foliage can't be seen, but a creature/object behind the foliage can be?)
There's no contradiction. I really can't see anything in that area. There could be someone up in that tree looking at me, and I would have no idea. Nevertheless, I can see telephone wires traversing the area behind the tree and the sky peeking through the canopy behind that.It seems to me that you are the one not following your own guidance. You're imagining an area of foliage with gaps big enough to see through and into the area beyond, but then applying the mechanics for Heavy Obscurement even though the presence of such large gaps conflicts with the description of Heavy Obscurement as effectively inflicting the Blinded condition.