Andy-
I don't know how you're planning to hook up your links, but looking at your drawing, if the cable is to the right side and each carb is connected by a separate link to the T, it seems like the carb on the left would open slowly in the beginning then more rapidly, while the one on the right would open very quickly with just a little cable pull. If you tie the left and right carbs together with a crossbar and link the T to the left carb, you'd get the first case but the with the two carbs synchronized; link to the right, second case.