If you have two words for the same variable in a view, you can join them into a single word. This works with a Defined variable and a Shadow variable, or with two Shadow variables. (It is not possible to have a variable that is defined more than once in a view so the third possibility is ruled out.)
To join two words, move the first word over the second (using any tool except the Lock tool, Magic Wand or Delete). When the pointer is over the second word, its shape will change ( 
) to indicate that the words will be joined. When you release the mouse, the two words will become a single word at the position of the second word. All arrows emanating from the two old words will now emanate from the single new word. If you try to join two words representing different variables, the words will overlap, but nothing else will happen.
The inverse operation of joining is accomplished by putting a new Shadow variable on the view, and then using an Arrow tool to draw new connections.
The Merge tool allows you to join together words representing different variables, and also attach an existing variable to a valve. The Merge tool is discussed in more detail above.
