Do we really want to have the legacy provider as opt-in only?

[Salz, Rich]

    >>    DSA
    > 
    > What is the cryptographic weakness of DSA that you are avoiding?
    
    It's a good question. I don't recall the specific reason why that was added to
    the list. Perhaps others can comment.

The only weakness I know about is that if you re-use the nonce, the private key is leaked. It's more brittle than RSA-PKCS, but not as flawed as RC4.

I think this should be removed from the "legacy" list unless someone can point out why it's like the others in the list.