I don't think a comparative tutorial explaining how to use both screen-readers is necessary.  I think it should be done in instructional material to point out that screen review in NVDA, for example, is similar to usin g the JAWS cursor in what it does and that you use the numpad for screen-review in NVDA while in JAWS you use the navigation commands you use while in the PC cursor.  If the person knows the JAWS cursor, he will understand what is being said.  If not, it won't matter.  The point is that the person learn screen .review and what it is using NVDA.

The same is true for object navigation.

And speaking of object navigation, I just did a tutorial on object navigation whhich I sent to the list a number  of days ago.  I found one very minor mistake in describing a dialog being worked with and another minor mistake.  I'll correct them and send the tutorial again.  I'll explain the error and lack of clarification in detail when I send the tutorial again.  The mistakes are minor and may not affect anyone's understanding, who has used the tutorial so far, but they should be corrected. 

Gene