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Yes; you can put me in a position where I have experiences such that, given those experiences (and given my noetic structure), the rational thing to do is to give up the purported defeatee.
Sometimes, however, I already believe the defeater (or, strictly speaking, part of the defeater), but do not initially realize its bearing on the defeatee.
So merely giving an argument with premises a sophisticate accepts is not sufficient for providing a defeater; the premises must also be such that once I see the conflict, rationality requires that I give up the prospective defeatee rather than the premises.