Well no doubt reasonable people can disagree. I find that when my sugars fall into a groove, I very rarely deviate more than +/- 8 points from my average blood sugar for any given time of the day. It is very predicatble. I've posted my averages on this board before for pre-breakfast, post-breakfast, pre-lunch, post-lunch, etc. Because it is so predictable, risk of hypo etc. is somewhat minimized.
I know where my sugars are at at almost any time of the day without checking; although I do check frequently any way. The troubles I've had with hypoglycemia occur when I venture off the path sort of speak. Either there is a change in schedule, change in routine, change in diet, or a change in dosage -- any of the aforementioned can cause me trouble if I'm not careful. Most of my really bad hypoglycemic episodes occurred while I was awake in the afternoon, not at night while I was sleeping.
I control my diabetes through my diet, three different types of insulin, and heavy weights exercise. As I've mentioned before, Levemir, Humulin R, and Humalog is what I use to keep myself in check. My meals typically consist of a protein and a vegetable. If I eat any fast acting carbs, it is typically not more than a tablespoon of it. I use the weight lifting to help me maintain my weight (I'm 6'1 and ~185 lbs). If I start to drop weight, I'll snack on nuts (eat two full oz of nuts for a mid-morning snack and an afternoon snack). I also drink a lot of heavy whipping cream. The cream gives me lots of calories without too much of a spike in blood sugar (cream has hardly any carbs to it).
I very rarely cheat on my diet. In fact, in 9 years of eating this way, I cannot think of any time where I went and cheated on my diet because there was something that I just "had to have". I'm very meticulous about how I manage my diabetes. Like I wrote before, when you've had this disease as long as I've had it, your margin for error is small. The body can withstand years of abuse, but damage does occur on some level. It's just a question of how long before the damage manifests itself.
It wasn't till I took control of my own diabetes that I achieved these results (with significant help from the Bernstein book). I've had many endocrinologists over the years give me bad advice (congratulating me on piss poor a1cs, giving me a poorer standard for test results than the non-diabetic because I was diabetic, trying to push me to a statin for cholesterol levels that were only slightly out of range, etc.) Quite frankly, I don't trust doctors. It wasn't until I took control of my own diabetes that things started to turn around for me, but that was not because of any of the endocrinologists I've seen.
Once again, I was breaking down 9 years ago. Today, any damage that I had has reversed. I have no gastroparesis, neuropathy, vision damage (diabetes related), etc. Kidneys and organs all still work like a non-diabetic, etc. After 31 years, I feel very fortunate. I attribute this to running my sugars at a level of a non-diabetic.
Perhaps conventional wisdom may switch one day about tight ranges on blood sugars, but for me, what I do works.