The people in the ACORD study were also on extremely high-carb diets and taking glucose lowering medications including insulin. Many of the people died of coronary incidents which may have been contributed to by hypoglycemia. It is almost impossible to avoid hypos with high carbs and lots of insulin. Bernstein's theory of small numbers explains this much better than I can in the space of a post.

As Eddie said, most of them had already experienced the devastating damage of long-term poor control and the target A1c of 7 isn't anywhere near normal A1c. I would try to get below 6.