[Tex/LaTex] siunitx: protecting lines with text from being formatted as number

Question

The siunitx package has already been extremely helpful to me for formatting tables containing numbers and I now use the S-column in nearly every table of my thesis.

However there is one problem:
In the heading lines of the table (between toprule and midrule) there is text and variables and units which regularly produce errors when columns are formatted with S[...] so that I have to manually enclose every one of those texts with round brackets }.

I wonder:
Is there a way to exclude a whole tabular line from the S-column formatting and mark it as "text" (as if every cell would be written in "{}")?

Answer 1

The TeX \halign primitive, from which tabulars are built, is column-oriented. As a result, row operations are not trivial to implement. As a result, the current answer is that there is not a simple way to achieve what you'd like. I will of course consider possible approaches.