Several Wick contractions on same variable with \vphantom

Question

I'm attempting to parse the second half of this question. The solution is for self-contractions, but I would like to have more than one contraction between one variable and another. An attempted solution I had was

\documentclass{article}
\usepackage{simpler-wick}
\begin{document}
$\wick{\c1A  B \c1 C \c3 \vphantom{C} \c3 D}$
\end{document}

but there is a tikz error with vphantom and the rendered image is this:

Is there a way to render just a single C with two contractions coming out of it?

Answer 1

I know nothing about wick and simply played around:

\newdimen\wickgap \wickgap=2pt % gap between adjacent wicks
\newbox\wickbox
\def\doublewick\c#1#2\c#3{\setbox\wickbox=\hbox{$#2$}
 \c#1{\phantom{\kern-.5\wickgap\copy\wickbox}}
 \kern-\wd\wickbox\kern.5\wickgap
 \rlap{\copy\wickbox}
 \c#3{\phantom{\kern.5\wickgap\box\wickbox}}
 \kern-.5\wickgap}
$\wick{\c1A  B \doublewick\c1C\c3 \c3D}$

Answer 2

Another way could be something like this (the C in \phantom{C} is only needed for the correct height of the box), but it is probably evn more hacky than Heiko's approach and you would require manually adjusting the spacing for every letter, which is not optimal:

\documentclass{article}
\usepackage{simpler-wick}
\usepackage{mathtools}
\begin{document}
    $\wick{\c1 A  B \c1 C \mkern-4mu \c3 {\mathclap{\phantom{C}}} \c3 D}$
\end{document}