do you know if this can (or should) be applied retroactively to existing works? Is it needed on every static web page or just blog articles? Perhaps a new thread on authorship is in order.
We did - it makes plenty of sense to me.
and if the infringers are on page 1 and the artists are on page two ..all the "head shots" in the world are not going to get a click through to the real owner ..the click will have happened the page before..
I agree with this. However, my results were that within a couple of weeks of using authorship mark-up. the infringers were no longer outranking the original author.
Stopping the infringers head on is a frustrating effort - they seem to grow like weeds. I only have time to go after the worst ones, or the ones that start to steal rankings.