It's possible, I've driven several and done a few on a foil myself. You have to have a driver that is really in sinc with the skier. The skier calls out the around the boat with a hand signal and the driver response with the same (we use a circular fist motion above the head).
This is done by cutting out wide to one side and then having the boat driver turn back in to and underneath the rider while the rider continues around behind the boat. The boat then continues in the opposite direction with the rider.
I've never done it, but did see video of a double round the boat with two foils doing the around the boat. SICK!
Here is a pic:
http://airjunky.com/temp/RTB2.JPG JT