Test document

\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage[dvipsnames]{xcolor}
\usepackage[style=authoryear-comp]{biblatex}

\addbibresource{biblatex-examples.bib}

\makeatletter

\newcount\testgl
\testgl=0
\begingroup
\obeylines
\long\gdef\test{%
  \begingroup
    \testgl=1 %
    \obeylines\@test}
\long\gdef\@test^^M#1^^M#2^^M{%
    \ttfamily%
    \def\scr@tch{}%
    #1\par%
    \color{Red}#2 %
    \ifnum\pdfstrcmp{\expandafter\trimspaces\expandafter{\scr@tch}}{\strip@ltr#2}=0 %
      \color{Green}OK!%
    \else%
      \color{Red}No :/%
    \fi\par%
    \hrulefill%
    \gdef\scr@tch{}%
  \endgroup%
}
\endgroup
\def\trimspaces#1{%
  \if\relax\detokenize{#1}\relax
    \expandafter\@gobble
  \else
    \expandafter\strip@trailing@spaces
  \fi
  {#1}}
\def\strip@ltr#1 {}
\def\tmpa#1{%
  \def\strip@trailing@spaces##1{%
    \strip@trailing##1\qnil\strip@trailing#1\qnil\strip@qnil}}
\tmpa{ }
\def\strip@qnil#1\qnil#2\qnil#3{#1}
\def\strip@trailing#1 \qnil#2{%
  #2#1\qnil\strip@trailing}

\def\scr@tch{}%

\renewbibmacro*{cite}{%
  \edef\tmpa{%
  (\the\numexpr\currentgrouplevel-\testgl\relax)%
  <\the\value{overallcitecount}/\the\value{overallcitetotal}>%
  [\the\value{citecount}/\the\value{citetotal}] }\tmpa
  \xdef\scr@tch{\scr@tch\tmpa}}

\usepackage{unravel}
\unravelsetup{
max-action =  500,
max-output = 3000,
max-input  = 3000,
}

\begin{document}
% leaking counts with \cite (probably the smuggling?)

\test
A \cite{sigfridsson,worman,nussbaum}
A (3)<1/3>[1/3] (3)<2/3>[2/3] (3)<3/3>[3/3]

\test
B \cite{sigfridsson}
B (3)<1/1>[1/1]

\test
C \cites{sigfridsson,sigfridsson}
C (5)<1/1>[1/1]

\test
D \cites{sigfridsson}{worman}
D (5)<1/2>[1/1] (5)<2/2>[1/1]

\test
D \cites{sigfridsson,sigfridsson}{worman,sigfridsson}
D (5)<1/3>[1/1] (5)<2/3>[1/2] (5)<3/3>[2/2]

\test
E \cites{sigfridsson,sigfridsson}
E (5)<1/1>[1/1]

\test
A \cites{sigfridsson}{worman}{geer}
A (5)<1/3>[1/1] (5)<2/3>[1/1] (5)<3/3>[1/1]

\test
B \cite{sigfridsson}
B (3)<1/1>[1/1]

\test
C \cite{sigfridsson,worman}
C (3)<1/2>[1/2] (3)<2/2>[2/2]

\test
D \cite{sigfridsson}
D (3)<1/1>[1/1]

\test
A \cites{sigfridsson,worman,sigfridsson}
A (5)<1/2>[1/2] (5)<2/2>[2/2]

\end{document}