@Drake:
well hancock DID turn magellan into stone, and he took down luffy with ease, and hes obviously stronger than luffy.
Just as ZKaiser already pointed out: He was turned to stone in a moment that was comic-relief.
For her power to work, it has a lot to do with the attitude her enemy goes into the battle with.
People who just look at Hancock as a beautiful doll, will be turned to stone for sure.
But I'm pretty sure if he see's her as a serious threat things will be different.
Nontheless I have to admit that not enough has been revealed about this fruit, yet…
Is her power just stopped by chaste thoughts or could you, for instance cancel it with mere will power?
may I ask where it has been shown ineffective on more experienced fighters?
Well, Momonga!
I have to point out that when I say "experienced" I don't automatically mean strong.
Somebody with a lot of experience with devilfruits and how they work is enough to stand against her Pertrification.
blocked by someone who is physically weak? ehh, no? it only wont work on people who are already negative like Ussopp, and so far I havnt seen many other people who are near as negative as Ussopp, it seems like her power could defeat pretty much anyone we've seen this far except him.
Where in the hell did I state that it could ONLY be blocked by weak people?
Of course both PHYSICALLY weak and strong people could block her attack.
But it could happen that a physically strong fighter with weak WILL could be inferior to a physically weak fighter with strong will (just as seen with Usopp)
And I'm not even sure if we can talk about willpower here…actually it's just extreme pessimism...
and fodder should be predestinated to be pessimistic, since they are in the danger to get owned any second!
I agree that Usopp's "special attitude" was pointed out to be not that common.
But just in theory, I doubt he's the only one.