People often say that hit points aren't meant to represent real injury to the character. But then, what are they supposed to represent? Falling back on things like endurance and morale are really poor excuses, because hit points simulate those things even more poorly than they simulate injuries.
In times like these, I think it is worth asking the people who wrote AD&D, and read the source document:
Gary Gygax et Al said:
Each character has a varying number of hit points, just as monsters do. These hit points represent how much damage (actual or potential) the character can withstand before being killed. A certain amount of these hit points represent the actual physical punishment which can be sustained. The remainder, a significant portion of hit points at higher levels, stands for skill, luck, and/or magical factors. A typical man-at-arms can take about 5 hit points of damage before being killed. let us suppose that a 10th level fighter has 55 hit points, plus a bonus of 30 hit points for his constitution, for a total of 85 hit points. This is the equivalent of about 18 hit dice for creatures, about what it would take to kill four huge warhorses. It is ridiculous to assume that even a fantastic fighter can take that much punishment. The same holds true to a lesser extent for clerics, thieves, and the other classes. Thus, the majority of hit points are symbolic of combat skill, luck (bestowed by supernatural powers), and magical forces.
I'm afraid you'll have no chance to discuss how poor of an excuse HP is, as both authors have now passed on to the planes beyond. However, this poor excuse has been the foundation of HP and the game since 1977, or over 30 years. And as such it has so much room to be used properly, without the unbelievableness of someone taking fourteen axe hits and whistling merrily along as they climb a 50' cliff.
It doesn't seem that different to me. If HP was only mental or only luck or only whatever, a week of bedrest wouldn't be required in 1e, 2e, 3e etc to fully heal. The barbarian could just get screamed at by the Bard until he was healed.
And herein gets to the heart of the matter: 1e, 2e and 3e HP recovery was redonkulously slow by mundane means, and only accelerated by divine magic or potion means. Thus, the recovery mechanic was unbelievable and incongruous with what HP were defined as. THIS, more than anything, is where the confusion has arisen over these 30+ years about what HP are and how HP work.
It's an amusing thing to note where we hang our "this is less believable" hat (fourteen axe hits vs having our stamina refreshed). Familiarity and first impressions have lasting impressions.
Dear WOTC 5E game designers,
Please put an entire page explaining the core definition of Hit Points in each of the core handbook.
It may not have been a full page, but as evidenced by the quote from the 1e AD&D PHB above, it was in there. Maybe a full page will ensure everyone is on the same page (no pun intended). Quote the 1e PHB as well on that page.
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Ob: the title of this tread, YES, I agree. Believability is likely a better word than "realism." There's even a quote about that in the magical 1e PHB.
Call HP regaining "recovery" rather than healing may help...
And maybe reprint this paragraph as well:
Gary Gygax et al said:
A few brief words are necessary to insure that the reader has actually obtained a game form which he or she desires. Of the two approaches to hobby games today, one is best defined as the realism-simulation school and the other as the game school. AD&D is assuredly an adherent of the latter school. It does not stress any realism (in the author's opinion an absurd effort at best considering the topic!). It does little to attempt to simulate anything either. ADVANCED DUNGEONS & DRAGONS is first and foremost a game for the fun and enjoyment of those who seek to use imagination and creativity.
peace,
Kannik