As much as we want to have every shot to result in a DRT with no suffering on the part of the animal, to expect that every time is unreasonable. There are sooo many variables that can come into play. I believe that being unfamiliar with exactly how high you need to hold on a deer to execute a high shoulder shot, after a lifetime of targeting the vitals, is one of those variables in this case. The fact that this is your first time to experience this says a lot of good things, Paul, so don't lose faith.

Also, to echo the remarks of brother Franchise and also not wanting to start a bullet battle, but I think an expanding bullet would have been more effective in this case. I feel they offer more room for error on thin skinned game and is all I use for them. A WFN hard cast placed high in the shoulder would have anchored him, and likely would have made mush out of his internals had it been place there. But, there is an area high in the chest cavity that I call "no man's land" and I think an XTP or other expanding slug would have had better effect in this case.

We live and learn from our experiences, and nobody's perfect.