SAump wroteONE: The rulebook states that there are eight exceptions that allow a batter to leave his batter's box during his time at bat.
which helps your argument, HOW?
SAump wroteTwo: The rule states he must continue to stay in the same box throughout the batter’s time at bat. Otherwise, I am wrong and rule should read either box, or allowed to switch from one to the other.
Where in the Rule does it say he must remain in the SAME box "throughout ..."? Ain't there that I can see. So, I'll pick "Otherwise, [you (SAump) are] wrong."
SAump wroteThree: Which rule allows him to leave after any pitch, a called strike or a ball? None. A batter then may not, by rule, switch places in the batters boxes after every single pitch. Sorry to disappoint you.
Default condition in Baseball: if it is not, by Rule, prohibited - it is permitted. There are darn few exceptions to this principle: can't think of one, off-hand. Absent a penalty [of which there is NONE here, unless a delay of game is created], no reasonable person can even argue for an implied prohibition.
I'm NOT disapointed: your lack of knowledge or insight into the Rules and customs of the game of baseball as shown in this thread is exactly as I have come to expect from you.