diff --git a/Tools/TimePlot.hs b/Tools/TimePlot.hs
--- a/Tools/TimePlot.hs
+++ b/Tools/TimePlot.hs
@@ -736,6 +736,12 @@
   "     showing the number of utilized machines and how this number is composed of",
   "     utilization by different jobs, make your trace say '>job-JOBID'...'<job-JOBID'",
   "     and use -k job 'within[-] count 1'.",
+  "     Explanation: if you specify -k REGEX 'within[.] SOMETHING', timeplot will",
+  "     take all tracks matching REGEX, split each track around the first '.', giving",
+  "     a 'supertrack' and 'subtrack' (e.g. customer.John -> customer, John), ",
+  "     group the events by supertrack and for each supertrack draw a graphical track",
+  "     using the plot type SOMETHING. It's up to SOMETHING to do something with these",
+  "     events, e.g. 'lines' will simply draw several line plots, one per subtrack.",
   "  'acount N' is for activity counts: a histogram is drawn with granularity",
   "     of N time units, where the bin corresponding to [t..t+N) has value",
   "     'what was the average number of active events or impulses in that",
diff --git a/timeplot.cabal b/timeplot.cabal
--- a/timeplot.cabal
+++ b/timeplot.cabal
@@ -1,5 +1,5 @@
 name: timeplot
-version: 0.3.0
+version: 0.3.1
 cabal-version: >=1.6
 build-type: Simple
 license: BSD3