I understand your frustration. When a key concept is not clear, how can you possibly understand all the related ideas in their proper context? Perhaps seeing some other people's ideas of wobble-pairing might help?

http://www.web-books.com/MoBio/Free/Ch5A.htm
http://www.blc.arizona.edu/courses/m...sePairing.html
http://www.med.uottawa.ca/patho/devel/

BTW, sometimes I comforted myself by thinking about the qualifications necessary to become a professor. Seldom is teaching ability even considered. This guy is past his threshold of competency. If you maintain your efforts to exceed his standards (whatever they might actually be), you'll likely obtain a superb grade on the course.

Lar