* In a message originally sent to All, Ken Frost stated:
-KF> I was under the impression that the catcher's balk was to
-KF> be called anytime the catcher came out too soon. I am very
-KF> much interested in the correct ruling on this.
-KF> ---
 
OK I received a reply from MLB but apparently they didn't read
the question.  They just sent a photocopy of the rule book page 
and said "this should answer your question" and of course, it
didn't.  They did circle the entire text of 4.03(a) - which
says -
 
"The catcher shall station himself directly back of the plate.
He may leave his position at any time to catch a pitch or make 
a play except that when the batter is being given an intentional
base on balls, the catcher must stand with both feet within the
lines of the catcher's box until the ball leaves the pitcher's
hand"
 
"PENALTY - BALK"
 
The fact that they highlighted the whole section implies to me
that if the catcher leaves the box for purposes other than making
a catch or a play it's a balk (your assumption, too). 
 
I can recall in the late 1970s a catcher being called for a balk
because he jumped out of the box to try to bluff a runner back to
first.  Others in here say "no it only applies to an intentional
walk" -- I think not, because there would be no penalty for a
catcher violating that position.
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