Pentius
First Post
As far as their abstract nature...
I had a discussion with a player about hit points years ago, I forget the edition. I explained that I felt that hit points represented more than just damage taken, it was also exhaustion and luck. The DMG at the time backed me up on that. His reply was that "Well, then if that poisoned blade didn't actually hit me, why do I need to Save vs Poison?"
I didn't have a good response to that, and I still don't.
There are ways to get poison into a human body without cutting it open first. Maybe it's a contact poison, and a drop flew off the blade at the PC. The save would be to see if he was lucky enough to have it not hit, or land on his armor. Maybe he blocks the hit, or turns it aside on his armor, but a smear of poison tries to seep through.