I've tested long enough to know that my problem is the Dawn Phenomenon and if the Metformin gets that down early (question of timing) then I produce enough insulin to cope with the low carb load my body gets at lunch and dinner. When I reduced the amount of carbs from 100g per day to 50g per day to lose weight, I tested a lot and ended up with really sore bruised fingers. My GP doesn't ration me on lancets or strips but he has advised me to just test if I feel off now. However yes, it is best to test to establish your own pattern and which veg and fruit for example spike you. I can eat strawberries but not blueberries, blackberries or raspberries. I can eat carrots but not parsnips. Once you've established patterns then you can ease up a bit.