Resting many times per day

[The Blow Leprechaun]

The argument can be made that a "day" is not 24 hours. In Writing a New Spell into a Spellbook, the process is specified as taking 24 hours. Presumably, if a day was 24 hours, they would have used the term day (since it's used so liberally elsewhere); so, how ever long a day is, it isn't 24 hours.

If you assume a day is 8 hours, then you'll always have new spells after 8 hours of rest. Of course, your spells with "days per caster level" durations will be affected, too... but I suppose that's the price you pay.

Yeaah, I suppose you could argue it, but I'm not sure it has a lot of merit. Reminds me of the invisible cat argument CS Lewis gave, "If there was an invisible cat in this chair, we wouldn't be able to see him. Since I can't see anything there, there must be an invisible cat in the chair."

Personally, I think if it says a "day" it resets at midnight/dawn/whatever fixed time you decide, and if it says "24 hours" it means literally, 24 hours. So if I used it at 3 in the afternoon, I can't do it again until 3:01.

 

[TessarrianDM]

We used to use the "get up, use up spells, rest 8 hours, study/pray, go again" mechanic, but we switched over to "x spells per calender day". So, everything resets at midnight, with divine casters preparing theirs at specific times during the day (dependent upon deity) and arcane casters able to prepare new spells after 8 hours of rest, once per calender day.

 

[werk]

We used to use the "get up, use up spells, rest 8 hours, study/pray, go again" mechanic, but we switched over to "x spells per calender day". So, everything resets at midnight, with divine casters preparing theirs at specific times during the day (dependent upon deity) and arcane casters able to prepare new spells after 8 hours of rest, once per calender day.

You didn't say which you prefer and why.

 

[TessarrianDM]

As the DM, I definitely prefer the second interpretation (x spells per calender day). It means the players must pay much closer attention to budgeting their spell use, or that they must spend more of their treasure and/or time buying or creating disposable magic items such as potions, scrolls, and wands. It seems to slow power creep some.
With a large group of characters (9) they have ample spellcasting ability (4 primary: a Cleric, Healer, Cleric/Wizard/Rogue, and a Mystic Theurge; 2 secondary: Paladin and Ranger). When we were doing the "multiple rest stops/day", the Monk, Fighter, and Fighter/Rogue had several encounters where everything was pretty much dealt with by the spellcasters before they had time to get in range. Now, the players are much more tight-fisted with their spells, sometimes going through multiple combats in a single day and using 50% or less of their prepared spells. Often, they hold on to more powerful spells rather than use them, "just in case".

 

[Fifth Element]

[A wizard] must choose and prepare her spells ahead of time by getting a good night's sleep and spending 1 hour studying her spellbook.

This implies that wizards can only recover spells by sleeping a full night. Not during the day, mind you, but night. The core RAW only seems to address recovering spells after sleeping/resting at night. I don't think that should be taken literally, but it certainly goes to the intent of the designers.

My brain is telling me there's some rule about more rest than 8 hours within a single 24-hour period having no more effect than just 8 hours of rest. But I can't recall what that's in relation to, if it even exists at all.