Goal: I want a macro that changes the math font of only subscript and superscript. In TeX terms, I think this means I want to change only S, S' styles, which are typeset using scriptfont.
Graphically, I'd want
to be displayed as
Tries: I've been trying to do it the TeX way; that is, something like
but this fails miserably, as scriptfont and the likes seem completely ignored by LaTeX. It seems that LaTeX only allows to make distinctions on the fontsize, with
Nota: I was first interested in this as a real-life case, but I'm not even sure I'll need it any longer; I'm just really wondering what the answer is.