Conversation so far:
When did Bill Edwards, the football coach, retire?
Edwards retired in February 1973 after 39 years as a coach and administrator.
Did Bill Edwards coach football?
Bill Edwards was an American football player and coach.
What was Bill Edwards, the football coach, wife's name?
Bill Edwards wife's name was Dorothy.

Question: How many teams did he coach?
Self-contained rewrite: How many teams did Bill Edwards coach?