Don't know if this will help, but I have two thoughts on this.
1) I believe MDI does not implement tiling and cascading on minimized windows, so you might be able to minimize the window prior to the action, then restore the window after the action.
2) I also believe that the tiling and cascading of windows calls the windows resize and move methods, so you should be able to write methods that only resize and move the window under conditions that you specify.
Hope these help.