The following example shows tabulary is over-wide if p is used (but m works)
\documentclass{article}
\usepackage{tabulary}
\def\x{one two three four five six seven eight nine ten }
\def\xy{Red \x. Green \x\x. Blue\x. }
\def\xyz{\xy\xy}
\begin{document}
\noindent
\begin{tabulary}{\textwidth}{p{5cm}LL}
\xyz&\xyz&\xyz\\
1&2&3
\end{tabulary}
\noindent
\begin{tabulary}{\textwidth}{m{5cm}LL}
\xyz&\xyz&\xyz\\
1&2&3
\end{tabulary}
\end{document}
The following example shows
tabulary
is over-wide ifp
is used (butm
works)A user suggests
Which looks eminently plausible, although this code hasn't changed in any substantial way since last century...
Recording here. More analysis required on what the real intention was (although the current behaviour is clearly wrong)