Does customer focus automatically generate good customer service or are they separate activities that need separate attention? How come?

Yes, it helps generate good customer service because the focus is to the target (customer).  

Customer focus doesn't automatically generate good customer service unless you make your action plan and put it in action.

It is like you were asked to look at a subject, so you looked at it but if you did your observation and give your comment on how to improve it then that's what will give you the best look of it.

Yes, provided that observations made to meet customer satisfaction are attended.

CF is like a culture - which contributes to success of a business as it is directly attending the customer with purpose to ensure that all deliverables of Company meet the requirement of customers, i.e. Customer satisfaction is met.