\setuphead
  [chapter]
  [header=empty,
   footer=empty,
   command=\johnchapter,
   numberstyle=\it]

\def\johnchapter#1#2%
  {\vbox
   \bgroup
   \vbox
   \bgroup
   \baselineskip=\getvariable{johnchapter}{baselineskipone}
   \bgroup
     \getvariable{johnchapter}{fontone}%
     \getvariable{johnchapter}{text}
   \egroup
   \bgroup
     \getvariable{johnchapter}{fonttwo}%
     \getvariable{johnchapter}{between}%
     \getvariable{johnchapter}{author}
   \egroup
   \endgraf
   \egroup
   \centerline{\vrule height .25bp width 4.25in}
   \expanded{\blank[\getvariable{johnchapter}{before}]}
   \hbox{\it#1}
   \expanded{\blank[\getvariable{johnchapter}{after}]}
   \bgroup
   \getvariable{johnchapter}{fontthree}
   \baselineskip=\getvariable{johnchapter}{baselineskiptwo}
   \leftline{\getvariable{johnchapter}{title}\getvariable{johnchapter}{stopper}}
   \leftline{\getvariable{johnchapter}{subtitle}}
   \endgraf
   \egroup
   \egroup}

\setvariables
  [johnchapter]
  [baselineskipone=15bp,
   baselineskiptwo=30bp,
   fontone=,
   fonttwo=,
   fontthree=,
   text=,
   author=,
   between={~~---\kern5bp},
   before=3.050in,
   after=.4in,
   stopper={,},
   title=,
   subtitle=]

\setuplabeltext[chapter=Chapter~]

\def\MyChapter#1#2#3#4%
  {\setvariables
     [johnchapter]
     [title={#1},
      subtitle={#2},
      text={#3},
      author={#4}]
   \chapter{#1}}

\starttext

\chapter{Investing for Income}

\input knuth

\page

\MyChapter
  {Investing for Income}
  {Safely and Effectively}
  {``It's a funny thing about life; if you refuse to accept anything but the best, you very often get it.''}
  {Somerset Maugham}

\stoptext
