In theory David has made shot placement quite clear. Obviously his 40(even years) of experience has given him the authority, and we should all be grateful this board has members like David who are willing to provide good guidance on whathas taken him years ongathering his knowledge.

On the other hand, when the time comes to put what you've practiced to the test--this is a whole different ball game.
We have all made mistakes, a common mistake made shooting at the 'real thing' is not 'following thru'. Moving the bow arm away to quickly,to see where the arrow hasstruct (or missed)--another good reason why shooting with BOTH eyes provide100% vision, as against the 50% vision you get when one eye is closed.
A 3D target is great for practicing shooting at thevitals of an animal--and should be used, but when the real mccoy stands before you, shot placement now becomes only 'part of the equation'. Many more ingredients are now included, that of zero sound,stealth, focus, staying calm, drawing your bow,picking a spot, following thru, controlling the nerves--it'ain't as easy as target shooting anymore. Of course the lucky breaks happens every now and again, but don't ever believe you're guaranteed an animal because you'vemastered a 3D target--it's not always that way.
Ihave seen quite a few Professional Target Shooters miss their share of big game animals--yes I have.
By the antis, the likes of PETA, we are misrepresented--not because we have a weapon in our hand makesit a signed deal. Certainly not, it takes more. We're tested on every shot, our talent and our skill and when we stand behind that animal to document the result--"We have darn well earned it".