Exclude User from Activity Stream in BuddyPress?

<?php
add_action("plugins_loaded","bpdev_init_sm_mode");
function bpdev_init_sm_mode(){
    global $current_user;
    if(is_user_logged_in()) {
        get_currentuserinfo();
        if("someusername" == $current_user->user_login) {
            remove_action("wp_head","bp_core_record_activity");//id SM is on, remove the record activity hook
        }
    }
}
?>