Those Guinness draft cans have the carbs listed as 9 for 12 oz, which is a shade less than 19/ pint...
I'm not sure why the discrepancy but I'm using Calorie King for Guinness Extra Stout (6% alcohol) 16 ounces, a pint. It's actually says 18.7 grams CHO.
You all are working such nice, insightful bolus algorithms. I think pizza is in our future. One of you is going to crack this.
Oh I did crack the pizza obstacle, but everyone around me gets irate. I order a large pizza for myself and just eat the toppings and leave the crust. It led me to invent my own recipe for "Brian's Pizza Pie Pie."