If you didn't take insulin your body would have a whole lot of defences to stop your glucose levels from getting too low . Why do you think that is?
Your brain requires glucose
The first mechanism is to stop secreting insulin ; this happens in the low 4s and natural insulin 'switches' off quickly unlike injected insulin.
As the glucose falls glucagon is released, then other hormones that help raise blood glucose.
It's not until the next bit that the brain demands some glucose and a non insulin user starts shaking, sweating , becomes anxious and knows jolly well that they need to eat something.
With recurrent hypoglycaemia the threshold for these events becomes lower and in people who have used insulin for a long time (or had lots of hypos) many of them may be lost .Many of us no longer get strong 'autonomic' hypo signs.
As your glucose falls lower if you underwent testing you might find that you were less likely to be able to do certain cognitive tasks well , and your reaction times may decrease. The main reason for the driving regulations
There are some people whose brains seem to become habituated and adapt to lower levels but their brain still probably doesn't function as well in all tasks , especially those more complex tasks that demand more fuel like decision making.
Eventually the reduction of glucose to the brain means you become confused, may get blurred vision, become sleepy, irritable, aggressive etc .Because your brain is habituated to low glucose levels, this happens to you at a very low level it is a known thing, you aren't unique and it's one of the reasons most doctors are keen for people not to get into this territory because there isn't any safety net left.
I think that you are indeed continually close to the edge of that cliff .