Q:

macro for cmidline results in staircase

I'm doing a table with booktabs:
\documentclass{article}
\usepackage{booktabs}
\begin{document}

  \newcommand{\crI}[2]{\cmidrule(#1){#2}}

  \begin{tabular}{@{}lllll@{}}
    \toprule
    \multicolumn{1}{c}{} & a & b & c & d  \\ 
    %\cmidrule(lr){2-2} \cmidrule(lr){3-3} \cmidrule(lr){4-4} \cmidrule(l){5-5} 
    %     \crI{lr}{2-2}      \crI{lr}{3-3}      \crI{lr}{4-4}      \crI{l}{5-5}     
    q1   & 1 & 2 & 3 & 4   \\ 
    q2   & 1 & 2 & 3 & 4   \\ 

    \bottomrule
  \end{tabular}

\end{document}

I made a shortcut \crI for the underrules \cmidrule, but they result in a staircase.
With the upper line commented out, I get:

With the lower line, however, I get:

A:

\cmidrule looks ahead to see a following \cmidrule to put them on the same line, the shortcut defeats that. You could duplicate the definition and make it look ahead for \cRI but unless you are doing lots of these, that will probably take more characters than you save using the shortcut

