Fabian, thanks for your response.
i did try it. as far as i can see, stored procedures cannot return result set at all... i hoped to get an official verification for my findings. and maybe any work around.
about the network traffic: the result would be the same with or without stored procedure, but the request would be much smaller. sending a request like: "call sp1(x,y,z);" is much smaller than a very large bulk of statements. of course, the more critical point is to avoid unnecessary re-compilation of a large and complex bulk of statements, that should be able to execute many times during a single second.
in mssql, and mysql, procedures do able to return multiple result sets. i don't know what is the standard sql2003 about it. do you think it worth a bug\feature report?
thanks, again.