Well, if it's not SS, it's a really close twin! If your height and bloom size match the AHS, and your scapes are well-branched, sturdy, and above the foliage, I'd say you've got SS.
Here's a picture of my SS in 2011.
and here's a picture of it in 2014.
It is one of my favorite daylilies and one that I think will always have a spot in my garden! Everything about it is right in my wheelhouse