Crossbows inflict no Strength penalty or bonus. It's implied in the Getting Started section of the PRD, as there's no mention of Strength modifying the damage of a crossbow, but instead can penalize your damage with a bow.
You are indeed correct.
From the PRD:
PRD -> Equipment -> Weapons:
"Projectile Weapons: Blowguns, light crossbows, slings, heavy crossbows, shortbows, composite shortbows, longbows, composite longbows, halfling sling staves, hand crossbows, and repeating crossbows are projectile weapons. Most projectile weapons require two hands to use (see specific weapon descriptions). A character gets no Strength bonus on damage rolls with a projectile weapon unless it's a specially built composite shortbow or longbow, or a sling. If the character has a penalty for low Strength, apply it to damage rolls when he uses a bow or a sling."
Crossbows neither benefit from Str bonuses, nor suffer penalties for low Strength.
This is correct, the crossbow has nothing to do with the strength of the user.
Except for the fact that you can only use it once in your lifetime, yeah, it's good. :)
... and that is the entire point, and why it's a good ranged back-up weapon for a Wizard. It's slow, but requires little in the way of training, ability or physical conditioning to use to full effect.
Rez
That's also why it's a terrible weapon for anyone else
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