For your information: why the left button works the way it does in Zwei.

[Daniel L. Weinreb <dlw at MIT-AI>]

Every month, somebody asks us why the left button in Zwei behaves as it
does.  I am tired of sending out personal messages on this topic, so
here is the answer one last time for everyone to read.  The
single-click-left in the Lisp Machine editor currently selects the
window on which you click, but does not move "point" to that spot.  The
reason for this is that sometimes you want the window to be selected,
but you do not want point to be moved.  If point is in a useful
position, and you just want to select the window without losing that
position, you can just click left on the window.  If clicking left were
to both select the window AND move point, there would be no way to just
select the window.

It appears that some people prefer the way it works now, and others do not.
There appears to be a fundamental conflict here, and there seems to be no
option preferable to the current setup.