the subscript is higher than in
So how does one set a function with dash and subscript correctly?
I would input
Beside this: it's a feature of TeX, not a bug, that the subscript position change if there is also a superscript. See Appendix G of the TeXbook. But you can change the fontdimens:
The change is global, so if you want to revert it you will have to save the original values. There is also a package