Capt. Claret,
Bang on. Neither does "request traffic".
Cynical,
You should have a flight plan in for entry to the Class C anyway, so next time, try the standard taxi call to Para Gnd without saying "request code" and I'd lay odds they still give it to you.
Everywhere else with the same local procedure does.
Drift;
You put a plan in to fly IFR, they know you're coming so no need for notifying with "XX Centre, ABC IFR taxi". They are expecting your call. Once you've made a taxi call, there's a 10 min sarwatch in place for your departure, so no "XX Centre, XYZ Departure" either.
'Spose some think it sounds cool...