DS goes as soon as he wakes, also, but I still put him on the potty and he almost always goes again...? Anyway, I've gotten a pee/poop combo every morning this week, even though I'm almost sure he's already peed by the time we get him on the potty.
As for misses, I remember reading somewhere that EC is not like formal potty training where the goal is to get 100% into the potty. It's just keeping a connection and the communication lines open about what the baby is doing so that when they are old enough to walk/crawl to little potty, then they can do so themselves. My philosophy of EC is just to not let the baby forget what they were born with: the knowledge of when they were eliminating... So when I have 'misses', I don't think of them like as 'misses' - and I still grunt with him even if he's going in his dipe. (my mom really does NOT get that part!)