Ken,
Clayton and Fortin are two of my favorites to study.
In terms of Clayton... I've learn a lot on ramping up the energy and power of my opening deck copy from him.
I remember the first time I read his piece with a headline referring to bold-faced liars (don't remember the exact headline), I had a mental image of Clayton lifting the reader out of his chair by lapels and talking to him nose to nose. It was a real fast attention getter for me.
I also started using more sidebars and callouts in my copy once I started studying Clayton.
And what I've learned from Michel Fortin... well, that's another thread for another time. Let's just say I've learned a lot from him too.
Take care,
Mike