Reading this I suddenly came to remember that the artillery branch during the european "30 years war" and "100 years war" as we call them up here wasn't national at all.
In fact the artillery units was more of a "commercial enterprise" much like mercenaries, hired by the different sides in the conflict and rarely had any connection to the nation or king they were fighting for, except for the gold they recieved.
Given the fact that they were independent units they were able to drill and hone their skills to perfection, without interference from any other units.
They even had their own guild system.
