As I'm converting this table for my NPC generator, the thing that bothers me most is the extraordinarily high likelihood of an intelligent sword being in play. I mean, 1 out of every 4 swords??
However, when taken in combination with the aforementioned %'s on alignments, it really means that 1 out of every 10 (25% *40% = 10%) will be compatible with a given party. Based upon that, the likelihood of a serious problem sword (say, top 3%) is actually (3% * 40% * 1% * 1% -->> Int 16, 17; align 40%; Special Purpose: 1%, Max Languages: 1%) which comes out to 0.00012% or 1 in 833,333 swords. One of these would be nearly impossible to keep control of, frankly. A +1 sword in this category would be an Ego 36 which would require a character with both 18's in Int and Cha if at 1st level, so only likely for a Paladin. This would be a weapon ya just take straight to Mordor without taking it out of the bag of holding (sheathed of course).
Even a toning down of these odds to an ego of 24 (+1 sword with 3 abilities, 16int, 5,6 lang) is still 1 in 2,500. Using average stat rolls (~4 on a d6) means that even a first level character could control an Ego 24 sword (Int + Cha + Lvl = 12 + 12 + 1).
Most of these weapons would be little more than a nuisance or things simply left behind (because no one can pick them up without dying).
As you say, due to alignment restrictions only a portion of intelligent swords (and other weapons; 5% of them in 2E) are actually usable by the PCs, but they still should be pretty common. In 1974 OD&D all magic swords were aligned and intelligent. Similar ratios existed then- 65% being Lawful, 25% Neutral, and 10% Chaotic. In 1E AD&D they reduced it to 1 in 4 and introduced the same more complex alignment table which 2E uses.
But it's clear that the original intent was for them to be commonplace, and for them to give Fighters additional special abilities and options to use, especially at higher levels as the party found more of them.
My only issue with the whole Alignment damage thing is that there's no way to determine the alignment without actually picking it up. This means, back to the original odds, there's a 10% chance your low level character is going to die just looting, which seems... um... rough.
Detect Evil works, right? Or the old trope of paying a sage for information, assuming the DM allows players to do things like using tongs or rope or other objects to pick up a magic weapon of unknown properties and haul it out of the dungeon without actually touching it.
The random tables aren't a very good tool for telling you what the game's magic item distribution should be like.
They don't describe the game as it is- published adventures typically don't have random orcs dropping +3 long swords (even though overall, most such adventures have magic items be more common than treasure tables would indicate). It seems almost impossible not to conclude that curated magic was intended, with an eye for magic items that are both "level-appropriate" (whatever that means) and shore up important weaknesses- many magic weapons, potions, wands for the wizards, and defensive items for AC and saves.
Yes. It's important to remember that TSR D&D originally expected the DM to "thoughtfully place several of the most important treasures", which would "consist of various magic items and large amounts of wealth in the form of gems and jewelry" on each dungeon level (Gygax, The Underworld & Wilderness Adventures, page 6), so those hoards would always be in addition to randomly generated treasures. While the issue of PCs having too much treasure started being discussed pretty quickly, and Gygax in the 1979 DMG gave famously stingy advice and guidance on limiting treasure, making it hard to identify and take home, taking it away via taxation and price inflation, etc., the expectation was still always that the DM would be taking an active hand and deliberately placing a large share of the magic items, rather than just relying on the random tables to generate them.
This isn't really about the magic distribution, more about the chance of intelligent swords in the campaign and how much of an issue they'll likely be.
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As has been pointed out earlier in this thread, a lot of the really good modules, (Temple of Elemental Evil, Giants Trio, etc) have both sentient swords and really good loot. For instance, playing through the Giants (G1, 2, 3) you can come away with Gauntlets of Ogre Power, Hammer of Thunderbolts AND a Ring with 3 wishes on it... and that's what I can recall us missing on our playthrough (I'm the groups accountant and had to balance the books so I ended up reviewing them to figure out what we actually got).
The unusual swords are really as means to assist fighters and other non-casters to pick up abilities they don't normally have, not really as a means to derails things. So having a 10% of a usable sword/weapon show up seems rather appropriate given how little warrior classes can actually use in the grand scheme. As I pointed out, there's a shockingly low probability that a usable high ego sword will appear (unless finagled by the DM)
Yes. I think it's reasonable design to keep the chances low for a really powerful sword like that to appear randomly, though certainly at higher levels it seems clear to me that the DM would be expected to curate and "thoughtfully place" such weapons as major prizes in adventures they write.
That said, "conservative" players are ones that have failed to realize that roughly half the xp a character gets during an adventure is presented not in blood, but coin and magic. Gygax himself admits that he tended to be a bit more generous than what he advices when DMing.
Remember that in 2E XP for GP is an optional rule, and XP for magic items is only for CREATING them. As opposed to 1E and 0E, where XP for treasure was the main source, and XP for magic items was just for keeping and using them.
In 2E the core rules were roughly half XP in a given adventure from monsters, and half "story awards" for achieving goals/completing adventures.
Uh, I'm arguing they're not as common as they're statistically supposed to be. Go through any module and count out the number of +1 (or better) swords there are, and then count the intelligent ones. Again, statistically, 1 out of 4 should be unusual.
If I had to hazard a reason why it's lower than it should be, I'd say that edition creep made it less of a necessity to even out the fighter classes. The Encyclopedia Magica has an enormous catalog of gear for melee that simply wasn't there for 1e.
I suspect the real reasons we saw fewer intelligent magic weapons in play and in published modules than the magic items rules indicate should have been found are some combination of:
A) The rules for ego battles and control are a pain in the butt to track and mildly annoying to resolve (Paul from Wandering DMs
analyzed them and simplified the math a while back, but it's still something the DM & player have to track during every session).
B) Having an intelligent, talking weapon in the party means functionally an additional NPC the DM is expected to RP regularly.
C) Due to the above factors, Gary and other designers figured it was better to let individual DMs "thoughtfully place" them. ie: curate the placement of such weapons to their own comfort level.
D) Due to factors A & B, and from just observing that they didn't show up all the time in existing modules, designers after Gary who DIDN'T know that the original intent had been for them to be commonplace shied away from them just as we individual DMs usually did.
