I'm not sure what you mean by SA.
You're correct in that the steel is VERY soft. Well under what one would expect from a SAK. I think I might go for a walk through some trees in a while and try the butter knife with some light chopping to see how easily the edge will roll. It would be interesting. It stands up to paper, cardboard and whittling based tasks fine. Bone would be another fun material to test.
Regardless, it sharpens up just fine. I have piss poor sharpening skills but I have no doubts that with some more time I could make this shaving sharp. It's kind of funny, the idea of a razor-sharp butter knife. Hahah.
Does anyone know what they normally do in the way of heat treatment to average butter knives?