I think that Bakerloo has it about right, humans almost only learn when there has been death and destruction - and a court case.
I was impressed when travelling with SA Airlink in their J41s that I was personally checked about the exit and my responsibilities on each sector. In this country, when in the exit row, I cannot recall the last time it was drawn to my attention.
Yesterday, I was discussing this very subject with a fellow pax after the briefing and during taxi. He was Australian and spoke of a long haul when he had sat in the exit row and was well able to handle the door. He was turned out of his seat - before departure - and a woman with infant in arms was placed in it. This was the start of a trans-Pacific to South America and he found himself in the middle seat of the central block of five, he was not pleased!!
BUT he knew that, in an emergency, a woman is not going to place her infant on the seat and say, "Just a moment darling, whilst mommy dearest opens this heavy door and then I'll pick you up before all these lovely people trample us into the carpet."
Naturally, she will stand there with her baby in her arms and block the exit and I would not expect her to do anything other than protect her child. The crew must prevent this. I shall have to take a more careful look at exit row passengers.
As for the CAA pro-actively reading these forums and looking out to see what is being said? No. Even if they had the inclination, they will not have the time. We will have to take the time to write to them.