This may seem like an odd question to you but in the almost thirty years since home blood glucose testing has become widely available there has been a lot of debates between academic researchers on this topic. A recent study came out suggesting that if you had type 2 diabetes you could get your average blood glucose level (as measured by glycosylated hemoglobin, or HbA1c) to the same level whether you tested your blood glucose or not. I remember a similar study being done over twenty years ago to "prove" that self-blood glucose monitoring was "unnecessary" in type 1 diabetes. In these studies people with diabetes were randomly divided into two groups. Both groups were seen frequently by the research nurses and doctors and were encouraged to increase their pills and insulin to the maximum doses that could be tolerated without getting side effects, including low blood glucose levels (hypoglycemia). The results of these studies has usually been that both groups of subjects end up at the same level of HbA1c which, to the researchers, "proves" that self-blood glucose testing is not necessary.
I do not agree with that interpretation of those studies. It would be like dividing people into two groups and asking them to get through a dense forest on a pitch black night but only giving one group flashlights. In truth, both groups would get through the forest eventually. The group without the flashlights might take longer and would have more bumps and bruises from hitting unexpected trees, but they would all get through if they were persistent enough. To me that does not prove that flashlights are unnecessary, however.
As you can tell if you read The Diabetes Answer Book I really like comparing blood glucose self monitoring to carrying a flashlight. The whole purpose of using self-glucose testing is to allow you to know what your blood glucose is at different times of the day and night, before or after meals, and when you are feeling peculiar. It "shines a light" on the situation to let you understand what is going on. So whether you have type 1 or type 2 diabetes and whether you use pills or insulin or both to treat your diabetes a blood glucose monitor helps you to see how your blood glucose levels change in response to changes to treatment or to other things going on in your life. I bet you that if any of those academic researchers got diabetes themselves they would prefer to do self-blood glucose testing rather than just blindly increasing their doses of pills and insulin until they got side effects or got hypoglycemia!
Like most tools that are available to us in life they are only useful if we know how to use them and how to interpret the results that they give us.

