I try to avoid talking to my dogs, though I forget a LOT, and to not use a bunch of extra words they don't understand. I want them to know that when they hear a word from me it means something, and they should know what that something is. I would think that having someone talking to you all the time but only understanding a tiny bit of what was said and not even knowing if you were supposed to understand would be quite stressful.
We talk to the dogs constantly. But they know intonation. If I am telling them no, they recognize the tone I am speaking in and react... and all but a new adoption by my daughter are basset hounds... hounds are notorious for selective hearing.