The problem is that you never know at what point the elevation of blood sugar will be sufficient to cause complications, how severe they will be, and how soon they will come at any given A1c level, since each person’s physiology is uniquely sensitive to hyperglycemic damage. Studies of 50-year survivors with no complications have established that some people have a genetic protection against diabetic complications in the form of an insulation of their DNA against pathological changes. Other people have the opposite problem in that they are supersensitive to hyperglycemia, and I know from having observed my grandmother and aunts that the genetic profile of my family is highly disposed to developing complications, and yet somehow I have survived 52 years with the disease despite that. Were all the hypoglycemic episodes I suffered the necessary cost for that? No one knows, since we can’t conduct an experiment and see how I would have fared under one 52-year regimen or the other, nor can we determine how the genetic profile in everyone responds to which degree of hyperglycemia.
A friend of mine, who has now had diabetes for just 17 years and is in his mid-30s, has always had a very easy time controlling his blood sugar and always had much better blood sugar results than I did, since my physiology spontaneously produces huge variations in insulin sensitivity from one day to the next, so the same food, exercise, and insulin on Monday can keep everything fine but on Tuesday the identical program produces disastrous hypoglycemia, and then on Wednesday the same regimen cause massive hyperglycemia. Anyway, he is now blind and on dialysis after 17 years of excellent blood sugar results, and yet I’m still intact after 52 years of diabetes, despite having spent the first 20 years with a massively high A1c because that was in the era before home glucometers had even been invented.
Genetics is the key, and if you are hyperglycemia hypersensitive you have to decide which risk you will cultivate, complications or hypoglycemia? If you have huge spontaneous jumps in the body’s insulin response from day to day in addition to a large genetic risk, you are really in a difficult situation.