Thanks for your feedback.We each of us need to find what suits us best. My woe may not suit you since you are doing more exercise than me. FWIW I am on TWOMAD and I am using a small amount of diabetic medication (minimum dose) to allow me to eat some carbs. So i can eat a few potatoes and not see major spikes.
Are you testing yourself after meals? I test before the meal, then again at 2 hrs, then again at 4hrs after first bite. This gives good information on how suitable the food I eat is in terms of diabetic control, and it covers the long term falloff when I eat a meal with fat or high protein in it. Note that protein can also lead to blood sugar increase like carbs, but at a slower rate. Increasing fat delays the spikes, but otherwise does not normally affect blood sugar levels, so your need for protein shakes may still affect your sugars due simply to the protein. A rough guide is that protein is approx half the amount of carbs in terms of sugar effect.
Yeah I have to keep experimenting...