The description of these behaviors is termed the mechanism. When scientists are not provided with such a mechanism, then a description of a process, it's explanation, or it's understanding, is questioned. Astrology does not work with mechanisms. It works with relationships, patterns, tendencies, and interpretations. It does not always give a yes or no answer.
I hate the Drawing Canvas and I understand that it's not backward compatible, so I never use it. To turn it off in Word 2002 and above, go to Tools 4 Options, General tab. Untick Automatically create drawing canvas....
In Microsoft Visio 2010 or Visio 2013, when you click Fit to Drawing in the Size group on the Design tab, the page resizes. But a small margin remains between the edge of the page and the drawing.