% interface=en output=pdftex

\setuppagenumbering[state=stop]
\def\CapStretchAmount{0.3em}
\def\CapStretch#1{\def\stretchedspaceamount{\CapStretchAmount}\stretchednormalcase{#1}}
\def\stretchedbox#1%
  {\bgroup
  \framed [frame=off, offset=.5em, align=middle,
           width=broad]{\CapStretch{\sc #1}}\egroup}
\setuphead [subject][textcommand=\stretchedbox]
\starttext 
  \subject{feeling stretched feeling stretched feeling stretched feeling stretched}
    \processfile{tufte}
  \subject{feeling stretched}
    \processfile{tufte}
\stoptext
%finis
