Stupid Newb question about Extend Spell.

[EarthTremor]

I've been playing 3.5 for years and i'm still having to ask simple questions :)

How does Extend Spell interact with spells what have a listed maximum duration?

For example, the spell lesser vigor (Spell Compendium, pg 229) has a listed duration of "10 rounds +1 round/level [max 15 rounds]". Would an extended lesser vigor spell cast by a 3rd-level druid have a duration of 26 rounds, or 15?

[Shhalahr Windrider]

I believe that there's a Sage Advice or FAQ entry out there that states Extend Spell cannot extend the duration past the listed maximum. I'd have to do a lot of digging around to find the exact entry, though. Especially if it's not in the FAQ and in Sage Advice instead.

Personally, I think that's silly. By the same logic then, why should Extend Spell work on spells with fixed durations? The whole point of the feat is to make the spell last longer than the listed duration.
[hr]EDIT: Okay, it is in the FAQ:

The vigor series of spells (found in Complete Divine) raise an interesting question. Does the built-in maximum duration of each spell limitation override the effect of the Extend Spell feat?

Yes. Extend Spell still increases the spell’s duration, but only up to the spell’s listed maximum duration. Use either the normal maximum duration or the doubled duration, whichever is less. If a 7th-level druid used Extend Spell on her vigor spell, the duration could not increase beyond 25 rounds.

Also of note:

The mass lesser vigor spell has a fixed range (of 20 feet), which makes it eligible for the revised Persistent Spell feat in Player’s Guide to Faerûn. Does that mean a 17th-level druid could use a 9th-level spell slot to give nine creatures fast healing 1 for 24 hours, or does the built-in limit of 25 rounds make that pointless?

Unlike Extend Spell, Persistent Spell replaces a spell’s normal duration with a new duration of 24 hours. In this case, the effect overrides the normal maximum duration of the spell, so it would indeed grant nine creatures fast healing 1 for 24 hours (a pretty reasonable effect for a 9th-level spell).

At least this time the FAQ is consistent. Not logically, really, but insofar as the Sage actually remembered a potential point of contradiction and is ready to make a special exception.

I still think it's stupid.

[Lord Lorac Silvanos]

It is in the FAQ and I agree with Shhahahahahalahr Windrider.

The vigor series of spells (found in Complete Divine)
raise an interesting question. Does the built-in maximum
duration of each spell limitation override the effect of the
Extend Spell feat?

Yes. Extend Spell still increases the spell’s duration, but
only up to the spell’s listed maximum duration. Use either the
normal maximum duration or the doubled duration, whichever
is less. If a 7th-level druid used Extend Spell on her vigor spell,
the duration could not increase beyond 25 rounds.

[UserClone]

Shhahahahahalahr Windrider.

This made me giggle, because I always have to cut & paste his name for just this reason.