Great stuff, Greg!
I learned many important things from some of the great callers early in my 
career. Larry Edelman taught me to teach about "places, not faces" while 
teaching squares. This can also apply to contras. Ted Sanella taught me to 
first tell who we were to look for, then what we were to do with them. These two 
tips have proven very helpful when working with all dancers.
John B. Freeman, SFTPOCTJ