Boy...I've killed a bunch from a stand....and the way I see it...there's no real difference in kill percentage from my perspective. My kill ratio is probably about the same either way. Heck, I've even killed a couple shooting uphill at them.
The only real difference in aiming at them is if they are real close to you at somewhat of a steep angle. Most folks want to aim at them mid way up like a whitetail...but that is too high to start with. Hogs are more barrel shaped and there's more underneath than you can see....so if they are close aim 1/3rd up instead of 1/2.
If you are worried about 'the shield'....a shield that will really hinder penetration on lighter weight bows....here again is your target area to completely miss the shield.....its not a big area either.
Click Here So...if you want to hit the soft spot, its much easier from the ground, or having them out from your stand a bit and not having your stand real high.....however, there's not a lot of margin for error to completely miss the shield either way.
If you are 10 - 15 feet up and the hog is 15 yards away....you've still got a pretty good view of the entire body....its the steeper angles that hide more of what's underneath. Course, I don't like steep angles on deer either.
If your set up will allow....and you are just after hogs....8-12 feet is good medicine.