Originally Posted by
pabelfly
I kind of disagree with you there. This applies to all team members, so it's going to apply to both the Fighter that has no Spot and Listen, and the Ranger who has full ranks in both. If you've got a caster that wants to do stuff like alarms and whatever, this is less relevant, but if you want to use skill checks, this is pretty decent.
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I wouldn't pick Iron Will in of itself for a build or this ability, but there's a few different reasons to get it - classes like Incantatrix, Ur-Priest, and Runescarred Berserker require it, and you need it for the Reserves of Strength feat, among other less-likely use cases. If I got Iron Will on my build for some reason, this would be a nice secondary benefit I could pass around.