No it isn't. Point Buy is a mechanical solution to the simulationist problem of Vancian Magic.
I quite agree.
That it resembles nothing...
But on that I disagree completely. As I've pointed out, it also resembles for instance the way spells are composed in Zelazny's 'Amber' stories. And as I've also indicated, it strongly resembles the general feel of any narrative where in the wizardly character has mysterious reasons for not using magic most of the time, even when that reason is not mechanically the same as Vancian.
...not even the works of Jack Vance
And again, I disagree.
and playing a wizard who knows he's going to forget things when he uses them is painful.
I disagree. It is a lot of fun. One of my favorite characters of all time was a wizard. Besides which, this particular spin you've put on the mechanics is unnecessary and in my opinion its something of a misnomer to focus on it, because frankly, the simplistic way you are looking at not only doesn't make sense (explaining your problem) but isn't even fully supported from the D&D text.
The way Vancian casting is explained in my campaign world changes the fluff slightly but not the mechanics at all. Mortals are not themselves sources of power, and have only limited abilty to draw upon magical energies. Indeed, a wizard is unable to draw on more power than it takes to exstantiate a cantrip. For more powerful spells, a mortal must rely upon extensive art and lore. There is a science to magic, and spells must be engineered. To cast a powerful spell, a wizard must not only memorize the spell, but he must go through the rituals required to prepare the spell for casting. He must trickle power into resivores within his being the way water slowly backs up behind a dam. He must build wheels and engines of power, in order to with the small force he can muster leverage greater energies. When he's has finished the incantation from his spell book, the spell has been wound up like a spring and drawn taunt like a bow, needing only the Wizard to perform the short remaining ritual to release the power in a spectacular way. This is why when he casts the spell, he is unable to cast it again. And because preparing and using these spells is physically and mentally taxing, once he's prepared as many as he can, he must rest before he can prepare any more.
This is a tremendous amount of flavor that is far deeper and more interesting of an explanation that the simple 'magic works because the wizards wills it' that forms the majority of explanation in most other mechanical systems. It's an amazing starting point, and while I like the sorcerer class, on the level of how deeply the mechanics interact with the world, the wizard is just miles more interesting of a class. Musty tomes, forbidden lore, ancient libraries, arcane laboratories, and esoteric paraphenalia are all tied in detail to the class through the mechanics in a way that just no other system manages. Moreover, I would point out that the explanation I've just given has been supported in various places in the text by various editions of D&D, and unlike your simplistic explanation that the wizard 'just forgets', it actually explains the observed mechanics. For example, it explains how you can prepare a spell twice and why you an still cast one after having cast the other.
And of course, you can tweak the flavor in other ways without altering the mechanics as well, as suits you. The flavor explanation for the mechanics doesn't have to be perfect. There is no perfect flavor explanation for hit points or armor class either. But an abstract non-literal interpretation works quite well, and is in many cases more than worth it compared to the drawbacks found in more literal systems.
And most people don't find it helps the narrative structure either.
If this were true, then quite frankly, most people are wrong. I don't however believe it is true. I believe that its part of the secret of why D&D looms larger in the story of RPG's than other systems with supposedly more 'realistic' mechanics. Many people always dismiss it as 'nostalgia', but I've come to believe that that is an insufficient and probably insulting answer.
The fifteen minute adventuring day is an issue caused by the pacing of adventures not being fast enough.
No. The 15 minute adventuring day is an issued caused by the pacing being predictable and fully controlled by the players. It is a valid strategic response to any situation where you have ablative defenses and full control over when and where the encounter takes place. Hit points themselves are enough to cause the 15 minute adventuring day regardless of the spell system in use (which is why some others have identified it as a problem of Vancian divine spellcasting). If you have full control over when and where you fight, why ever go into battle with less than full hit points much less spells?
Any time the PC's don't have full control over when and where the encounters take place, you don't see 15 minute adventuring days, and frankly, any time that they do have that full control (Tomb of Horrors, for example), then you
should see the 15 minute adventuring day as the logical response.
It's not a question of the pacing. It's a question of whether things happen in the PC's absence. It's a question of whether the PC's enemies are proactive and also recover defenses in the absence of pressure by the PC's. It's a question of whether the PC's can always safely retreat to a haven whenever they want. If the PC's can't retreat to a haven at any time, if the PC's enemies are proactive and intelligent, if the PC's enemies recover during oppurtunities to rest, and if the PC's enemies engage in plans of their own and cause things to happen even when the PC's are resting, then you don't see 15 minute adventuring days. And contrary to your assertions, that's a lot of room for different narratives, and indeed probably covers the majority of source material that you'd draw inspiration from. The Ring Quest in LotR doesn't have the pacing of 24, but the adventurers also don't have unlimited oppurtunity to rest. Not only are they on a clock (albiet, one much slower than 24), but they have enemies who are actively seeking them out.
If it is not a valid strategic response to the problems that they are presented with, the players will gravitate away from the 15 minute day. And if you always present your players with things that force the 15 minute day as the optimal response, then don't be surprised if that is what you get (or wand of CLW abuse, as others have pointed out).
1e had its solution to the 15 minute day; rolling for wandering monsters every ten minutes.
I don't recall a fixed and universal schedule of when wandering monsters would show up. Rolling every 10 minutes is something that normally occurs only when the in certain high traffic areas specified by the text or when the PC's are doing something that actively draws attention to them. If camped in the dungeon in a location unknown to intelligent creatures, then I usually rolled twice a night. If of course the location was known or could be ascertained or inferred, then the intelligent creatures would plan an ambush or assualt as they best could - or would simply take the oppurtunity to grab as much loot as possible and flee in the night.
But once you get out of the dungeon, in order to keep the classes balanced you need an average of four fights per day.
This for example was roughly the expectation I remember in earlier editions for travel in the wilderness - one wandering encounter check every 6-8 hours.
Unless you're a commando unit in hostile territory...
Funny you should say that, but that's pretty much exactly a description of D&D's default assumption about play and in fact well describes certain classic campaigns and adventures (Dragonlance, Red Hand of Doom, Keep on the Borderlands, etc.). Let me ask you this question, if you aren't in hostile territory, why should we really be worried about this at all? If the PC's aren't in hostile territory, what is the likelihood that the ECL of a challenge is suffiicent to draw down all of their resources anyway? In non-hostile areas you are highly unlikely to see 15 minute adventuring days anyway, because the PC's will simply press on (especially if they know on a meta level that the likelihood of another encounter is remote). I mean, I presume that the adventures are going somewhere and doing something, and if they aren't, isn't that the real problem?
