Moving Around
-------------

   When you use `t' (`mh-toggle-showing') to toggle between show mode
and scan mode, the MH-Show buffer is hidden and the MH-Folder buffer is
left alone.  Setting `mh-recenter-summary-p' to a non-`nil' value
causes the toggle to display as many scan lines as possible, with the
cursor at the middle.  The effect of `mh-recenter-summary-p' is rather
useful, but it can be annoying on a slow network connection.