On Wed, 02 Mar 2005 13:17:02 -0800, Tim Rowledge <tim at sumeru.stanford.edu>  
wrote:

> Yes, it completely voids the 'direct' pointing aspect since moving from
> point A on your desk to point B and back will not neccessarily put the
> cursor back in the same place.
>
OTOH, they do make navigating on big screens a bit easier, it seems. A  
trade-off, here?

> At least they kept the 'tangential' property of the mechanical mice, so
> that moving your hand in an anatomically sensible arc corresponds to
> left-right.
>
Gosh. I never knew that. Just moved the cursor over a straight line  
left-to-right and back, checking the actual movement of the mouse, and  
indeed, it describes an arc rather than a straight line. Learned something  
again today (at least I know can go to bed knowing that my day was not  
completely spent in vain trying to cook up accounts for the taxman ;))