I'm rather intrigued. So, based on your 6-monthly Hba1C, you are confident, and so is your doctor, that your glucose levels are OK? You don't test before or after meals on the basis that you know your control of your glucose levels are fine?
How do you know how your body responds to different foods? How do you know which foods, at what time of day, will raise your glucose levels or not? I'm Type 2 and, yes, I test my glucose levels having bought myself a glucometer several years ago. I'm now prescribed meter and test strips because of the medication I now take which can cause hypos and so had some idea of how my glucose levels were.
The Hba1C is, basically, an average of your glucose levels but this will not show any peaks/troughs, ie spikes and low levels. So, an Hba1c would not show whether you've had spikes or a straight line and this is what worries me, in general. If your glucose levels were to be checked every five minutes, 24 hours every day, there would be lots of peaks and troughs, even in a non-diabetic.
So, I can't see how you can know your glucose level without testing.