diff --git a/runtime/doc/os_unix.txt b/runtime/doc/os_unix.txt
index 0b0f389..f875f16 100644
--- a/runtime/doc/os_unix.txt
+++ b/runtime/doc/os_unix.txt
@@ -28,10 +28,11 @@
 can be changed at compile time.
 (For forking of the GUI version see |gui-fork|.)
 
-Because terminal updating under Unix is often slow (e.g. serial line
-terminal, shell window in suntools), the 'showcmd' and 'ruler' options
-are off by default.  If you have a fast terminal, try setting them on.  You
-might also want to set 'ttyfast'.
+For historic reasons terminal updating under Unix is expected to be slow (e.g.
+serial line terminal, shell window in suntools), the 'showcmd' and 'ruler'
+options are off by default.  If you have a fast terminal, try setting them
+on: >
+	set showcmd ruler
 
 When using Vim in an xterm the mouse clicks can be used by Vim by setting
 'mouse' to "a".  If there is access to an X-server gui style copy/paste will