Hi Vans,
I'm Type 1 and have been for 30 odd years. Some very odd... :?
I limit my carb intake to about 30 grams a day; 6 grams for breakfast, 6 for lunch, 12 for dinner and the rest in milk for coffee.
I have found that blood sugar fluctuations have decreased a great deal; so less hypos not more. Also insulin requirements have come down.
One of the things that we hear again and again and again and again on this site is health care professionals, chiefly diabetic nurses and dietitians not knowing the difference between ketosis (a normal metabolic state where you are metabolising fat in the absence of glucose) and ketoacidosis (the dangerous condition where you are metabolising fats and protein in the absence of insulin). They are not the same. Ketosis is fine.
I find it surprising as well the number of diabetic 'experts' who do not know GCSE level information about diet in particular what 'essential nutrients' are. You will be told you 'need' carbohydrate - that is absolutely wrong. Certain processes in the body require glucose, but you don't need to eat it; your body is quite capable of manufacturing glucose through the process of gloconeogenesis (from breaking down protein).
An essential nutrient is one that our bodies cannot make themselves; so glucose (which makes up all carbohydrate) is not an essential nutrient and the amount you need to eat to live is zero grams.
Follow the Bernstein book and his dietary suggestions, keep testing, keep thinking about exactly how much insulin you need if you are drastically reducing your carbs and I bet you will find your control improves markedly!
Best
Dillinger