Excellent point. Another way to say this is that there observations and inferences. Observations are what we experience and inferences are what we think about what we experience. It is very important to clearly distinguish these as you say. It is possible to agree on what we experience, and if we do we have a common basis for discussing our inferences.
As you say it is very important to focus on a phenomenon, and our observations of it before we begin to develop inferences. And as you say, students will only learn, change their minds, based on their own conclusions from their own experiences. Telling them just doesn't do it.
Good for you!!