Although we had some super-secondary matches in the template library,
we had to rely heavily on our "new-fold" cost functions for building
models for target T0281.  We ended up with several slightly different
models that we have difficulty choosing among.

This is try19-opt2, which has the same 4-strand topology as model, but
has a bulge in the edge strand (as in model 1). This model scores
second with our unconstrained cost function.