It would be interesting to hang out with Randy Mosher, Ray Daniels, Chris White and Chris Graham for five days and play with the more sophisticated homebrewing systems. I couldn't personally justify the $2K price tag on the basis of learning/improving homebrewing skills, but if you have the dough then I can't think of a class with better teachers and five days won't disrupt your life too much.
I agree that Chicago is a hotbed of craft beer activity, lots to experience and I enjoy my too-infrequent excursions there.