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Why EUF-CMA without verification oracle is not equivalent to EUF-CMA with verification oracle?

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In the book we have talked about sEUF-CMA-secure with verification oracle being equivalent to sEUF-CMA-secure without verification oracle. The proof idea is simple. One direction is trivial. The other direction is proofed by this idea. For every adversary on sEUF-CMA-vq with max q-Verify requests, we can just guess at which Verify request the EUF-CMA-vq adversary is succesful. So we can simulate a verificaton oracle by always answering with Verify(m,t) = 0 for every Verify request except the last j-th one, which is hopefully our valid tag. Why we cannot argue exactly the same way for EUF-CMA?

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