John,
Sorry about that. I had thought that it had made it into the documentation, and I'm not sure how it was missed.
The quickest explanation is "Just use All Static." It has been the Simply Fortran default for a few versions now, and it ensures your program will work on a machine that doesn't have Simply Fortran installed. It pulls in the Fortran and GCC runtime libraries during the linking step rather than dynamically linking them.
I'll make sure it's documented in the next release.
Jeff Armstrong
Approximatrix, LLC