Question about Orca and gnopernicus.

["satyam" <satyanarayanamurthy tanikella gmail com>]

Dear List,
I have a question regarding gnopernicus, Orca and open office.org
Why there should be many screen readers?
is it possible to modify gnopernicus to use with open office.org?
I am asking this question since switching between screen readers become
difficult is it not?
Please throw some light on this.
Satyam.