It's fun as an experiment to let the dog express moods and what's on their minds at a particular moment through human concepts (words)
The main interesting aspect for me is to see what free associations the dog may make, like how something in the environment could trigger memories or reminiscences.
If my girl saw a big brown dog through the window for instance she may push the "Marley" (big brown friend of hers) button because it triggers memories of Marley, etc
Totally random example but you know, fun stuff may come out of it.
What I less like about this trend is how excited people are about grammar and tense. I think there's too much anthropomorphic emphasis on how a sentence is built and people expecting dogs to make whole sentences.
I don't believe in that.
I don't think dogs have rational conceptual discourse at all, I believe reminiscences of experience pop up/are triggered in their minds in a primitive way, then trigger the next one, a bit like dominos.
"Marley > play > outside" would be a likely series for a big brown dog trigger for instance, and could probably occur in any order actually.
But not "Marley is walking outside now. Daddy will take me outside after work. Marley is a nice dog. I love him."
That's human thinking.
I'll never have these at home though 😂
I don't have the patience and I don't think I'd learn anything groundbreaking.