@EMSTAR1892 Emma, the thread you have put your post on is six years old and I think John has long moved on. While a low GI approach can help a little bit in getting peak blood sugars down, you are still eating carbs, which will digest in due course and become sugars. As you suggest, having a fatty, low GI meal may help reduce spikes, but, once again, the carbs are still there and will have an effect much later on, when you've long passed the normal time for testing.
If you want to make sure that your HbA1c's are low, my best advice to you, which I am sure will be backed up by the majority here, is to reduce your total carb intake, irrespective of GI.
Sally