MULTIPLE CHARACTERS FOR A SINGLE PLAYER
This section is an idea that for many modern games is anathema--the very idea that a player could or should split his effort between two or more characters is almost scandal-worthy and players that seek to do so are sometimes accused of being power gamers, munchkins, or seeking to draw attention from other players.
This was not always the way of things. Hell, back in high school when I played AD&D second edition and various Palladium games, we often ran two or more characters at once. Our groups were small--generally three to four players at most, including the DM/GM, and running multiple characters was a way to fill the gaps that would normally be provided by extra players. Certainly we had primary characters that gained more focus, but even our secondary characters were played as separate individuals and fleshed out much more than would be your average henchman or hireling. Indeed, the book takes this very assumption: "In campaigns where there are only a few players...it is likely that each (good) player will have several characters." (DMG, 111)
Other assumptions, however, look at campaigns in a very different light than they are generally undertaken nowadays. The idea when Gygax was writing was that a campaign represented not a long-term series of adventures by a single adventuring group, but a "milieu," or fully-realized fantasy world that had an ongoing history in which multiple groups, players, and characters would take part. The idea, then, was that a character may leave his adventuring companions for a time on occasion to pursue personal quests and goals, and that his player would then have a secondary or tertiary character who could step in to fill the shoes of the missing character in the group. This secondary character would, of course, be a distinct individual who would very likely not be even the same class, race, and alignment as the character who had temporarily left.
As a side note, I often think it would be really awesome to play or run a game like this, and to a degree I have. My version of the Palladium Fantasy world has been ongoing since high school with multiple groups coming in and out over the years, but I've never done multiple groups in that world all at once. I started a version of an AD&D Greyhawk game that I would've loved to expand in this manner, but it petered out. Some day I'll pick it back up again. I do wonder if there's anyone out there who runs a true Gygaxian campaign in this style, but this section has really hammered home to me that the way we think of the idea of a campaign has drastically changed from the hobby's foundations, be it because gamers don't devote the kind of time to their hobby that wargamers once did, or due to a more Lord of the Rings epic story influence creeping in.
INTERVENTION BY DEITIES
There are games where deities are all over the place and directly involved with the lives of the PCs on a daily basis. Such games can be entertaining but they run a lot of risks--I myself ran such a game, though mine was a modern urban fantasy game wherein players were seeking to ward off the coming Apocalypse. The biggest danger one runs when running a game of this sort is that eventually one of the players will get fed up and demand to know why the gods don't just put a stop to this. In my game I made the players work that one out for themselves, but in any case, Gygax is pretty clear that this is not the intent of AD&D.
Despite the fact that books like Deities and Demigods give stats to the gods, the DMG is transparent in its stance that gods should be distant and aloof. Their involvement in the lives of PCs is generally limited to granting spells to Clerics. As the book says, "If an entreaty for aid is heard one time in 100, surely each and every deity int he multiverse would be as busy as a switchboard operator during some sort of natural disaster." (DMG, 111)
In general, even when deities do hear the call of PCs it will be to counter the direct involvement of a deific enemy--an evil or opposed god--and even then such aid will likely be in the form of sending powerful servants such as Archons to aid the characters rather than personally appearing, which only happens in the most extreme and dire of circumstances. Such an appearance might happen once in the entire lifespan of a player character, and then only if said character is exceedingly faithful and true to the precepts of the deity and to the deity itself--an absolute champion, a paragon of all that the deity represents. The book then presents a table of probability shifts based on how often the PC has asked for help, his behavior and the circumstances of the request. In the end, most player characters are going to see a 0-5% chance of the deity hearing their call, which upon reflection puts the percentage a bit higher than Gygax originally seemed to want it to be. From where I sit, it's best to ignore such tables altogether and let the DM just make a judgement call based on the needs of the campaign.
As a final bit of clarification and trivia, the book says that deities who are somehow "killed" off of their home plane (generally, on the Prime Material) aren't actually dead, but merely returned to their home. i see this as the first instance of what 2nd edition later clarified as the idea that deities who visit the Prime Material Plane are actually not the deity itself, but are avatars, physical representations of the true deity, who in reality is always on its home plane without a real physical form.
Next Up: THE ONGOING CAMPAIGN - SIXGUNS & SORCERY AND MUTANTS & MAGIC.