I would like to ask any of the many teachers at my school who took a lot of Latin if they had to learn the irregular case usages, sans prepositions, for some place names like Roma, Romae, etc. But, if I were to do that, I would just about guarantee that they would feel put on the spot. “OMG, that was eons ago, I can’t possibly remember how to say that.” I wasn’t asking them to say it, just to remember if they had studied that and I would start off b y asking them if they knew how to say “I was in Rome”.
That would be to see if they used the preposition plus place name or the special case. If the former, I would then ask if they had had to learn the special case form.
The reason for that would be to confirm (which I could easily do through reviewing traditional textbooks like Jenny from the 1i950s) that indeed Latin teachers tried to teach all the exceptions to the rule along with the rule.
But what would happen? The teachers would feel put on the spot. Why? Because that’s the way languages are taught catch the student making a mistake. The underlying thought is: if I correct them, they won’t make it again AND if they know the exceptions, that means they know the basics. Both are wrong.
Now ask someone who ACQUIRED a language such questions. All they’ll do is ransack their mind for how they would say whatever you asked. That’s b/c they have acquired the language in a natural way and wouldn’t feel put on the spot anymore than the teachers at my school would if I asked them, “What do you call that round container you put flowers in?” (answer: flower pot).