Swap the beginning and end zoom selection

[mishmatta]

I'm trying to swap the beginning and end zoom selection.  That way if you duplicate a slide, you can start the second slide's zoom where the first slide's zoom ended.

I wish I could include a screenshot to show you.  But imagine a square.  

 

A___________B

|                   |
C___________D 


On slide 1, I would like to start with the entire square as the start zoom, and then finish the zoom on just the letter A.

Then I would duplicate the slide, but want to start the slide zoom in the ending spot of slide 1, then zoom to the letter B as the zoom out.

I know I can do this manually, but trying to line up the section perfectly is tedious.  

I don't know if I'm explaining this right, but please let me know what your thoughts are.