Do you have any pics or drawings of those metal post clips you've used before Titmas?
My reason for setting the posts into the ground is to gain lateral stability without using knee braces.
You know, like I said earlier, any rot I've ever seen with posts set in to the concrete has always been at the surface, so my thinking is that with the concrete slope for drainage at grade, and the copper wrapped around the post, rot shouldn't be able to even start.