\def\wNone{0pt}
\def\wII{2pt}
\def\wIII{3pt}
\def\wIV{4pt}
\def\wV{5pt}
\def\wVI{6pt}
\def\wVIII{8pt}
\def\wC{100pt}
\def\wCC{200pt}

%
% Empty
%
\cals@rs@spec@begin
\cals@rs@spec@end\wII
\show\cals@current@rs@above
\show\cals@current@rs@below

%
% One element
%
\cals@rs@spec@begin
\cals@rs@spec@next\wC\wIII\relax\wIV  % length, borderT, borderB
\cals@rs@spec@end\wV
\show\cals@current@rs@above
\show\cals@current@rs@below

%
% Two elements
%
\cals@rs@spec@begin
\cals@rs@spec@next\wC\wNone\relax\wIV
\cals@rs@spec@next\wCC\wII\wVI\relax
\cals@rs@spec@end\wVIII
\show\cals@current@rs@above
\show\cals@current@rs@below
