Hi Mike - I know you asked for help in deciphering nutrition labels but I find using a scale works better for me. I use Calorie King to measure carbs, protein and fat by weight. I've found this to be more consistent and dependable than depending on the nutrition label. Calorie King allows you to insert the serving size by weight using grams or ounces. It also allows choosing alternate volume measures such as cups, tablespoons, teaspoons, slices and many others. I find weight to be much more dependable than volume for calculating the nutritional content of most foods.
The Calorie King program produces a standard nutrition label for your exact serving size. In addition to carbs, protein, and fat, it also reports fiber and calories.
I know that using labels might shorten the process but I find weighing using an inexpensive digital scale to be very consistent. My insulin doses tend to be better matched to my nutrition. I also keep a record of the insulin dosing I use for many of the common meals I eat so I can give the dose quickly and get on to eating.
The labeling system you showed as an example seems to invite confusion. Good luck. This is a worthwhile project. Matching insulin well to nutrition is complicated enough with timing, changing insulin resistance, and other factors. Adding the wild-card of inaccurate food measurements only makes it harder and also complicates analysis when things go wrong.