My bold.
I would be in favor of that too. Many precious sites already have such measure in place. Leonardo da Vinci's Last Supper and the Nasrid Palaces in Alhambra come to mind.
Visited the Sistine Chapel 4 times. Most recently last year during "off season". It was wall-to-wall" people. One could hardly move. I managed to snap a few shots inside the chapel. In this trip report, you can see them:
http://www.flyertalk.com/forum/trip-...entures-4.html
Just thinking outloud here...
+1.