Make new emph overlay-aware
Something along the lines of
\newcommand<>{\emph}[1]{\alt#2{\structure{#1}}{#1}}(I, personally, still would prefer to have another command for this, instead of \emph. In my environment, I have defined \textb{} for Jülich-blue text, and \textbb{} for bold Jülich-blue text. Defined along the lines of above's definition.)