Anyone else find it odd that the anti-head-shot people jump all over hunters who take head shots on deer and moose, but those same people will often recommend head shots on rabbits, grouse, etc.?
It is as if they think some species are more or less deserving of a "humane" heart/lung shot than other species. This is nonsense. An injured snowshoe hare will suffer just as much as an injured mule deer.
In the end, it is 100% up to the individual hunter to decide what they are comfortable with. I am comfortable shooting snowshoe hares in the head every time, out to about 80 yards or so. If a hare doesn't present a head shot, he/she lives (for a few more days, anyway). Based on this, I would not hesitate (and have not) to blast a deer in the head within that same range. A deer's head is far, far larger than a snowshoe hare's head.
If you can't shoot this well, or the situation creates conditions that make it difficult to shoot this well, then don't do it. Stick to the boiler room. Pretty damned simple.