Why is there a difference between the open macro function and the open menu item?

I’m don’t understand why the macro open command behaves differently than the menu open drop down.

EXAMPLE: (In FIJI);
Set up these files and run from the desktop. to get this:

//Begin Macro
//Differences between the open macro and the menu command.
//Drag this macro to ImageJ and run it
wdir = File.directory;  
open("A.txt");
waitForUser("Now open A.txt from the menu");
//End Macro

A.txt =
2 2 2
5 5 0
5 2 2

It looks like the old ImageJ editor gets called in the first case. I’d like to understand when the old ImageJ editor will be called.

Thanks for your thoughts
Ron DeSpain