Constructivists have to see that our human world cannot be explained by rules, nor can it be fixed by simply prescribing the right set of new rules to follow. Constructivism is a way of seeing the world. When you see the world that way, you will design things and make decisions consistent in a new light. That means, to me, respecting people's automony and meaning-construction ability. Actually, I have been disappointed in the discussion on constructivism over the past few years.
People make their own meaning.
But it's my job as a teacher to make sure these people learn certain things. Knowledge needs to be transmitted. You cannot control that, and it's certainly not a direct transmission of anything. They have bought into the same kinds of dualities and ultimate worldview as the positivists. I reject the false dualities that underly such discussion.