I do have a tendency to shoot to quick although I've been bow hunting for a while. I'm just starting to second guess things alot after not harvesting the last two.

According to the diagram above, If you hit anywere under the backbone to about 2/3 down then you are going to hit lungs. So you really can't shoot high if you are under the backbone, right?

Also, is it correct to say that the heart is totally masked by the shoulder if the deers legs are perpendicular to it's body?

Both of these deer were shot out of a treestand. One was 5 yards from the base of my tree and the other was about ten. both were quartered away. Is it possible to get a double lung at these close distances or should you go for a heart. That is where my confusion is. Where do you shoot it from the tree stand. I try to guestimate at the angle that will take it through the heart but I fear I'm only getting one lung.