This is probably an ignorant question, but do Type 2 diabetics -- the vast majority -- really monitor their glucose and inject it if low? I thought Type 2 was really about how sensitive the cells are to glucose, not a lack of glucose being produced.

Yes, monitoring blood glucose is the main tool people with type 2 use to manage their condition:

http://www.everydayhealth.com/type-2-diabetes/monitoring-blood-sugar.aspx