[wp-hackers] Changing two variables listed in apply_filters hook

[Ted Balaban]

 Any Wordpress  function can be removed by a remove_filter 
using a hook in a plugin only if a do_action hook statement is 
inserted in the Wordpress function?

Any Wordpress function with a do_action hook statement inserted 
will be processed first by specifying a high priority (10 being low 
and 1 being high) in an add_filter statement in a plugin?  In this 
case the function added by add_filter will execute and the Wordpress 
function will not execute or not execute unless removed by remove_filter.