diff -r c51a9bd4cf09 -r 48e973251070 src/Doc/System/Sessions.thy
--- a/src/Doc/System/Sessions.thy	Sun Jan 06 12:01:09 2019 +0100
+++ b/src/Doc/System/Sessions.thy	Sun Jan 06 12:33:45 2019 +0100
@@ -740,10 +740,8 @@
   similar to the ones above. Searching the above option names in ML sources of
   \<^dir>\<open>$ISABELLE_HOME/src/Pure\<close> provides some examples.
 
-  Different update options can be in conflict by producing overlapping edits:
-  this may require to run @{tool update} multiple times, but it is often
-  better to enable particular update options separately and commit the changes
-  one-by-one.
+  Updates can be in conflict by producing nested or overlapping edits: this
+  may require to run @{tool update} multiple times.
 \<close>