This came up in a game today, so I want to double check if there is a FAQ against it.
Right now, Temporary Ability Score Bonuses/Penalties are very specific in what they increase and decrease. This means that people with Weapon Finesse/Agile Maneuvers still need to buff STR to increase their to-hit/CMB. Oracles with CHA-to-AC only gets AC from DEX and not CHA buffs, and other oddities like that.
Is this still how it works RAW, or is there an errata for this?
Thanks,
There are statements to the effect that the temporary ability bonuses/penalties are just simplified for ease of use, not because they are intended to change the way the rest of the game works. I'm not sure any of those statements made it to official errata though.
Temporary Ability Score Increases vs. Permanent Ability Score Increases: Why do temporary bonuses only apply to some things?
Temporary ability bonuses should apply to anything relating to that ability score, just as permanent ability score bonuses do. The section in the glossary was very tight on space and it was not possible to list every single ability score-related game effect that an ability score bones would affect.
The purpose of the temporary ability score ruling is to make it so you don't have to rebuild your character every time you get a bull's strength or similar spell; it just summarizes the most common game effects relative to that ability score.
For example, most of the time when you get bull's strength, you're using it for combat, so the glossary mentions Strength-based skill checks, melee attack rolls, Strength-based weapon damage rolls, CMB, and CMD. It doesn't call out melee attack rolls that use Dex instead of Str (such as when using Weapon Finesse) or situations where your applied Str bonus should be halved or multiplied (such as whith off-hand or two-handed weapons). You're usually not using the spell for a 1 min./level increase in your carrying capacity, so that isn't mentioned there, but the bonus should still apply to that, as well as to Strength checks to break down doors.
Think of it in the same way that a simple template has "quick rules" and "rebuild rules;" they're supposed to create monsters which are roughly equivalent in terms of stats, but the quick rules are a short cut that misses some details compared to using the rebuild rules. Likewise, the temporary ability score rule is intended as a short cut to speed up gameplay, not as the most precise way of applying the bonus.
A temporary ability score bonus should affect all of the same stats and rolls that a permanent ability score bonus does.
It is unclear if the same applies to temporary ability score penalties. YMMV & ETV. At my table, temporary ability score penalties affect everything that permanent penalties affect except for feat/prestige class/whatever prerequisites, mainly because the latter are a pain to manage at the table.