Good point BB about a damaged heart not pumping blood , but is that, in fact, the only way the lungs are filling up w/ blood ,or is it also that as the deer breaths, its sucking in blood from the holes in the lungs? Even if the heart stops, the chest is filling up w/ blood fast and essentially drowning the deer, right?

Personally I have not seen where a double lung shot deer will travel or die any less than one that was heart&lung shot.