@eeeefarm Thanks for clarifying the the terminology.
I had stopped bringing treats to the dog park for the obvious reasons, but over the past couple weeks I've been re-training Aten's recall at the dog park. (This dog park does not have large and small dog separation.)
Results have been very good. He still can be nippy when highly stimulated, but I'm more on him and leash him when circumstances warrant it. He really wanted the redirection it seems; he's a tightly bonded pooch and he welcomed re-establishing a tighter connection with me.
I've been getting a lot of comments on his impressive recall of late. A good reminder to me to that training never ends.
Thanks again for your time and insights.