Hi Marcy,
You can always give it a try and let us know how things worked out!
After all, the German shepard was a herding dog to long time ago, and the CsW is the group of the herding dogs (because the history of the GS).
I keep my mind open for everything, even herding with CsW
The number one capacity of a herding dog is not to finish the hunting... they just fixate, follow and 'herd' the cattle. It's like hunting, without the final step: the kill. Because the CsW wasn't further selected on this capacity to herd a cattle, they'll probably want to finish the game of hunting, by killing/attacking the catlle. I say 'probably' and 'most' CsW...
I think that if you train them if they are young to herd the cattle, they are able to do this. I don't know how your dogs react to other animals, but why not trying together with the lady you met?
It's not because a breed isn't especially 'designed' for something, that you can't try it with them... So I can't fully agree with Pavel on this...
Although it's true that the CsW will be a better dog for IPO then herding, of course
Liesbeth