Ok, so it seems like my main question would than be, when is it time to advance from the classroom or general area's to a trial situation? Or what would be a good stepping stone between the two?
Agility trials can be highly arousing. Dogs running, barking, tugging & growling on the tug (this can be a big trigger!) teeter banging, etc.
First, start with outdoor trials. Wayyyyy more space to get distance, turn away, and stay under threshold. Second, what about OB or conformation shows? Confo shows tend to be more lenient about unentered dogs. In both, dogs are calmer than at agility trials. Avoid flyball tournies!!