Of the ~20 some ARMER radios that I utilize on a weekly basis, typically, they will vote to the best site for reception (but we all know that). 1-009 and 2-002 are the sites that I most frequently vote to in Anoka County.
I dont know the specifics of my codeplug. My programming is generally limited to Unidens and analog Motorolas.
You may want to ask in the RR forum appropriate to the manufacturer of the radio that you are using. I have seen near identical conversations in each of the manufacturers forums regarding the programming of non-system equipment to scan a system without checking on as a user.
The caveat to that is that I believe that there are system commands that come to direct a transceiver to the most appropriate control channel. The motorboating you describe is a simulcast issue, which the makes up nearly every system in the metro.
TL: DR in my understanding, if you dont have a system key and a valid radio ID, you are better off using consumer hardware...