I hope you'll notice that I put it forward as a school of thought, I'd rather folk followed what I said in post #9. We are having a discussion and some environmental groups put it forward as a valid management practice.
That is true and English Heritage looked at the same thing calling it the use of Honeypot attractions so that, for example, Stonehenge would be promoted and hopefully the visitor pressure on Avebury would be lessened. However, they appear to have recanted and now look to open up the landscape around attractions in order to lessen the load. They have a grand vision of restoring the prehistoric landscape, open to the public, around Stonehenge now.