Personally I do necks shots as much as possible..
Sure you have a smaller window, but if ya miss that window( I have yet to) the odds of the game recovering from the wound and surviving is much greater.( Cause if ya miss the spine , juggular,vocals)all thats left is muscle.
Sure a behind tjhe shoulder shot has a better chance of killing, BUTTTT
You hit a deer too high too low too far back on a broad side shot, you end up wounding and losing it, with all the organs, loss of blood, huge exit wounds and internal damage, the deer will suffer greatly,and end up dieing a slow long painful death...