I hoped I had succeeded in conveying "reliably and predictably".
You had said that luck and divine favor were what let PCs survive long falls, with the implication that treating HP as mostly physical wouldn't allow that to happen; I thought you were objecting to the actual survival as opposed to a PC's expectation of survival, my apologies.
In that case, consider: you probably think nothing of hopping off a 6-inch-high curb or a foot-high step at the bottom of a staircase. You might be comfortable taking steps two or three at a time without a problem. You might even, if you're feeling brave, jump down a whole flight of eight stairs, but as a friend of mine discovered that can result in bruises. So you're roughly aware of your capabilities and know what will or won't hurt you.
Imagine some Olympic athlete, say a gymnast who's good at running and jumping. People who do Parkour for fun can leap up and down flights of stairs and drop a dozen or more feet unscathed with a duck-and-roll, so our Olympic athlete in top condition can probably do better than that. They likely have a good sense of their body, how much punishment they can take, etc. after training for so long.
Now imagine someone far above the Olympian in most physical area, who faces down giants and beholders rather than the parallel bars and balance beam. They've been eaten by a purple worm, crushed by a dragon, cut open by a troll, and more. They have a pretty darn good idea of what they can survive--and they know what can kill them, since they've probably had it happen once or twice and then came back from it. I'd say someone like that can estimate pretty well whether they can take a leap from a good distance. They might be wrong, of course--a 10-Con 15th level fighter with average HP
can take 20d6 and live but won't always--but the higher level they get the more a mere impact on the ground pales in comparison to other things they've faced.
That isn't to say that every PC would know their limits--I'd expect a ranger who sits in the back of the party shotting arrows at things and never takes significant damage to be much more cautious, for instance--but I don't see why anyone would object to a high-level frontline melee type saying "Dude, it's just a 100-foot cliff, I've fought demons that hit harder than that."
We're extremely far apart on what Process-Sim is definitionally (my definition of it maps to classic modelling in science which overlaps with Ron Edward's definition) and what it looks like mechanically in game systems that have a true Process Simulation agenda.
[...]
Thus, that meta-game logic (in play from a PC perspective and from an internal consistency/world-building perspective) is extraordinarily at tension with a world that attempts to be a process-simulator for real-world biophysics.
There's the problem, I think: we're not modeling
real-world biophysics at all. We're modeling a world with very similar rules and very similar starting conditions, but with some extra variables and some altered rules. That doesn't negate process simulation or immersion at all, it just means you have a different set of assumptions to work from.
For an extended example, let's look at the Star Trek movie
The Undiscovered Country, spoilered for length:[sblock]From the opening minutes, we're presented with things that don't exist and possibly can't exist, but they all have in-world explanations (however treknobabble-filled they may be) and they all work fairly consistently according to known rules. Given those known rules (replicators can't create living things, you can't hold shields while cloaking, etc.) and some sort of starting condition (warp core leak, oh noes!) you can extrapolate how things should work in a logically consistent manner, barring one-off plot contrivances.
So, in the movie, a moon explodes due to sabotage. Reasonable; ST uses antimatter for energy generation, so when it goes boom, it goes
BOOM.
The Klingons sue for peace. Reasonable; it's explained that there's a faction that wants to fight to the death, but you can't fight a war without weapons.
Starfleet sends Kirk and the Enterprise to escort the Klingon chancellor to the peace meeting. Acceptable; Kirk doesn't like Klingons, but Spock vouches for him and the Enterprise
is the flagship.
The ships meet up and the Enterprise appears to fire photon torpedoes at the Klingon ship with the databanks backing this up, yet all torpedoes are accounted for. Reasonable; hacking and sabotage are a thing that happens in ST.
It turns out that the ship that fired the torpedo was a cloaked Bird of Prey under the Enterprise.
Buh-
wha--?
It was long established that you
cannot fire while cloaked, multiple factions (including the Federation) had specs for cloaking devices and knew their limits, no advances in the technology had been made in the last 30 years by any faction, and from a plot-writing perspective "Thou shalt not fire or shield while cloaked" was treated as a commandment from on high. Yet the existence of a ship that can fire while cloaked is greeted with nothing more than raised eyebrows, hand-waved as "a prototype," and never brought up again.
Even for ST plot devices made of the highest-quality refined handwavium, that's a bit much. It isn't just a one-off appearance of some mystery race or a minor tweak to known canon, it's a major technology of a major villain with major plot ramifications breaking a
major rule both in- and out-of-universe...and the topic is shrugged off and the consequences are ignored. Even a casual ST fan in the theater can sit up and notice that that's not supposed to happen.
So, let's posit a ST roleplaying game. RPGs run on a different set of assumptions than fiction, in the sense that the stereotypical player is more likely to shoot the villain in the face than allow him to finish his monologue and, in the case of ST, would likely try to
squeeze every last iota of benefit out of warp drives and transporters (fly by the Romulans at Warp 6 and beam a nuke aboard while their shields are down!), sensors and weapons (jury-rig a phaser minicannon that fires on any Klingon it detects!), nd so forth. Players want to know how much water an
everflowing bottle puts out per round, how many settings a hand phaser has, and so on so that they can use those aspects of the world and know what's going on with the world around them.
If a GM were to run two solid sessions of the "Let's search the Enterprise to find out who fired those torpedoes" mystery, and when his players gave up at the end give them a small hint (neutron radiation) and say "Surprise! There was a ship there the whole time! It was cloaked, but it can totally fire while cloaked, 'cause it's a prototype!" he would probably be pelted with splatbooks. Same thing with some other blatant unexpected breaking of the world's physics, like some sort of massive probe that disables all Federation technology automatically because [plot device], for instance. What works in fiction doesn't necessarily work in a game.[/sblock]
It's the same kind of thing with D&D. We don't know what the power source for Vancian casting is (beyond the Energy Planes in AD&D), but we know that it can be cut off with an
antimagic field. We don't know how fighter types get to be so superhumanly tough that they can be chewed up and swallowed by creatures with stomachs full of flesh-melting acid and survive somehow, but we know
that they can survive and proceed to cut their way out. We don't know why someone with +50 Bluff is so persuasive--training? innocent looks? suave voice?--but we know that he can convince pretty much anyone of pretty much anything...and we cry foul if his
glibness is dispelled and his Cha dropped to 1 to leave him with a +10 Bluff and he can still get away with telling people the sky is green.
The same holds, on a much smaller scale and with much less melodrama, for individual powers and other abilities. You can tell the difference between a mechanic that makes sense in game, a mechanic that should make sense but the mechanics are badly-written, a mechanic that doesn't work but could with some minor changes, a mechanic that only works because plot, and other mechanics somewhere in the spectrum. HP-as-pure-meat doesn't work, but HP-as-mostly-meat works with some ancillary assumptions like "high level characters are superhuman" and "part of every hit is nonphysical" and so forth; HP-as-plot-shield doesn't work barring some fourth-wall breakage, but HP-as-mostly-plot-shield works with some ancillary assumptions like "only the last hit actually makes contact" and some rules tweaks to match.
We know the world's assumptions, we can recognize where flavor and mechanics don't quite match up, and if Star Trek geeks can quibble over canon then D&D geeks can certainly object to things that don't obey the D&D world's rules.
